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Mio DigiWalker C520t Review

Key Specifications

  • Review Price: £278.63

If you’ve ever had trouble reading a map you’ve probably considered buying a sat-nav system. And why not? They’re now so cheap and widely available that buying a low end device is a no-brainer. Soon, it seems, you’ll be able to pick one up for less than 50 quid at your local Tesco or ASDA.

It’s getting the big manufacturers worried and they increasingly have to come up with more innovative ways of persuading consumers to stump up the cash for their ‘superior’ high-end products. Just finding you the way is no longer enough.

Personally, I reckon they should be touting sat-nav’s green credentials. After all, having fewer people driving around aimlessly for miles with no idea of how to get to where they want to go is bound to reduce our national carbon dioxide output. But no, strangely enough it’s stuff like widescreens and traffic avoidance systems that seem to get the manufacturers excited.

Mio’s latest navigation device, the C520t, certainly fits into the latter category. It may well help you do your bit for the environment but Mio thinks its 4.3in, 480 x 272 widescreen is much more interesting. And it’s hard to disagree entirely, whatever you think of the current obsession with global warming.

The reason is that more screen real estate allows more information to be displayed without cramping the map view. I own a Mio C510e – the C520t’s predecessor – and in its navigation mode the information panel takes up too much room at the side of the screen. Here, though, the panel is just as large – if not larger – but there’s plenty of room for the map. A big improvement.

Speaking of improvements, the C520t also makes better use of this information panel. The first advantage is that you can hide it away altogether. Leave it on screen, however, and you’ll soon discover that the C520t packs in far more info than the bog standard route data that previous models were restricted to.

Press a button at the bottom of the panel and you can have it display nearby points of interest (POIs), along with your distance from them and roughly which direction you have to go to get to them. Double-click one of these POIs and the Mio gives you the option to automatically route you there – very handy if you’re running on fumes and need a petrol station fast.

Another option displays the next few turns on your route and you can also choose to display nearby traffic incidents here as well. In my experience, however, the C520t’s Traffic Message Channel (TMC) technology, which is built into the windscreen cradle, doesn’t work well at all – in fact I don’t think I’ve ever been in a situation where it helped me avoid a serious jam.

Address finding is one more aspect that has seen a tweak for the better. You can now enter a post code straight away when you hit the address screen, instead of having to select a city first. However, if you’re locating your destination by address, the data entry is still counter-intuitive: city first, street next and then finally street number.

Of course the C520t is more than just a bunch of improvements and it retains a lot of the features that made many of Mio’s previous navigation products such great value for money. As with all of the company’s products you get street-level mapping for nigh on the whole of Europe. These maps are preinstalled on the C520t, so no fiddling about uploading maps from the supplied CD – everything just fits in the device’s built-in 1GB ROM. And there’s a speed camera warning database with free updates provided for a year after purchase.

The C520t is also very good at providing driving instructions. Rarely did I find its TeleAtlas maps to be inaccurate, even in central London. Audio cues were clear and unambiguous, while the onscreen information and next-turn icons were always extremely helpful. It’s also pretty snappy at calculating routes, a feature that comes in especially useful when you stray off route or emerge from a tunnel and need rapid recalculation.

That’s not all. You can also use the device as a Bluetooth speaker phone while driving, upload your contacts to the POI database and use them in route planning, plus there’s a photo viewer and an MP3 player too. Disappointingly, the headphones socket isn’t the standard 3.5mm job so a regular pair of headphones won’t fit.

It isn’t all good news for the C520t, however. In fact for all of the improvements it seems that a few serious drawbacks have crept in as well. A bit like trying to produce a super-efficient green car that produces no CO2, but belches out black smoke full of poisonous particulates instead.

The main issue is the complete lack of external controls. Where previous models had volume and mute buttons, the C520t has unceremoniously dumped them in the search for clean lines and cool design. Now this wouldn’t be such a problem if the volume control was easily accessible from the map screen, but it isn’t. In fact it’s buried four clicks deep in a settings menu and this makes it a right royal pain in the rear end to change.

Another area where Mio has taken a step backwards is in audio quality. Compared to the C510e and other higher end sat-nav systems, the C520t’s speaker is poor. It sounds harsh, scratchy, grates on your ears and you have to turn it right up to hear it properly.

Performance is also a concern. Though the C520t sits at the top end of Mio’s range, it doesn’t pack enough punch in the processor department to cope with the demands of the software. Performance while driving is fine, fortunately, but navigating from screen to screen can occasionally be a frustrating experience with a three to five second wait at certain points. It seems to affect the speech engine as well, causing the voice instructions to sound slightly scrambled every once in while. If you remember the sound that agents made in The Matrix when they took over the bodies of unsuspecting bystanders, you’ll have some idea of what this sounds like. It’s very annoying.

All these issues are by no means the only ones. In testing I noticed many small but nonetheless irritating foibles. Occasionally it would get stuck in ‘2D’ overhead map view, even when it was supposed to be displaying a 3D map. The traffic events list on the information panel didn’t update frequently enough, leaving a five minute or longer gap before changing the distance figures. For instance, I drove around the M25 for at least 13km before an incident on the M1 changed from being 130 metres away.

Other irritations include a profusion of small and fiddly buttons for selecting critical functions, and a rather confusing two-pronged approach to searching for points of interest and displaying them on the map.


The trouble with Mio’s latest sat-nav is that it’s a case of two steps forward, one step back. The widescreen is very nice and Mio has made good use of the extra space, packing lots of much-needed improvements in. Alas, a bit like installing solar panels in an effort to do your bit for the planet while still driving a Hummer to the supermarket to do your weekly shop, these advances are undermined by the introduction of problems that simply weren’t there before.

And though the price of £278.63 is reasonable for a device equipped with a TMC receiver, it won’t be enough to persuade most consumers to upgrade or choose it over the similarly priced TomTom One XL, which also has a widescreen. I think I’ll join them, and stick to my trusty C510e.

Trusted Score

Score in detail

  • Value 7
  • Features 9

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