It's certainly a good idea, and it works well enough – if what you want to watch is lots of lifestyle TV, cartoons, documentaries and comedy repeats that is – but it's not perfect. The main issue is with the division of hard disk space, which is heavily weighted towards Anytime content. Select every single channel available, which you'll need to do if you want a decent selection of content to watch, and the box divides things up on a ratio of roughly 6:1 Anytime to personal storage space, which means you only get around 18 hours of recording space for normal TV to play with. The only way you can change this is to reduce the number of Anytime channels you have set to 'active' and, thus, potentially miss out on content that would otherwise have been recorded.
The box itself is bit on the noisy side too, and even in standby the fans make an audible whooshing noise. It's not something you'd want to have sitting in your bedroom, put it that way.
I think that Top Up TV is going to have its work cut out convincing the TV-watching public to take a serious look at its new product. The main issue isn't one of impracticality, or any particular hardware failing (though the hard disk issue and noise problems don't help), but simply that the selection of channels can't match Sky's for sheer quantity, range and flexibility. Only those who regularly watch channels like Discovery Lifestyle, Living TV, Hallmark and MTV may be swayed.
Fortunately, the Top Up TV package does have some advantages. At £139.99 for the package it undercuts the price of a Sky+ setup (from scratch) by £20 and has more hard disk capacity for recording. Even if you're only in the market for a Freeview PVR, a 160GB box like this for £139.99 is pretty reasonable anyway.
At £9.99, the monthly subscription is also cheaper than Sky's lowest priced package by £5. Next season you'll be able to watch Premiership football too for a reasonable £10.99 a month and for another fiver you can add a movie channel – PictureBox – into the mix as well.
For these reasons, Top Up TV anytime may be worth a look. It's well-priced and the hardware is capable – but only if you're interested in the channel mix.