After the performance behemoth that is Sandy Bridge (as seen in the MSI GT680), everything else is going to seem a tad underwhelming. Nevertheless, the quad-core Core i7 720QM powering the Envy 17 3D-1195ea is still one of the most powerful mobile processors around and will handle mosts task with ease.
In PCMark Vantage its lead over the dual-core Core i5 460M found in the XPS 17 isn't shown off properly, but more intensive use (like video encoding) will make full use of the extra physical cores and Hyper-Threading to provide eight virtual cores.
In 2D gaming, this HP's AMD Mobility Radeon HD 5850 can handle some reasonably demanding titles in lower resolutions. For example, Stalker: Call of Pripyat ran at a perfectly smooth 53fps on Maximum detail and DirectX11, albeit at 1,280x768. Crysis on High detail is pretty much out of the picture, but many modern games will at least run if you're willing to accept a few compromises.
It's worth noting that although the Envy 17 3D stays reasonably quiet even under load, its left side gets warm enough to act as a hand-warmer in winter, which is not necessarily a good thing.
Battery life is, unsurprisingly, the weakest area of the Envy 17 3D. Its 62Wh/5,225mAh battery only managed just under two hours in Mobilemark's semi-intensive Productivity test, while with the screen at full brightness, watching a DVD brought this down to just 55 minutes. Good luck watching a 3D Blu-ray without a power socket in the vicinity!
To be fair to HP, these kind of results are hardly unusual on a desktop replacement, but if you're looking for 3D on the go, the Acer Aspire 5745DG is by far the better choice - and considerably cheaper at £600. However, the Envy 17 3D does thoroughly trounce it in build, design, connectivity, performance and quality, not to mention actually sporting a Blu-ray drive.
A more viable comparison is with the 3D version of Dell's XPS 17. Using Nvidia's rechargeable wireless glasses in conjunction with a 17.3in, Full HD, 120Hz display, you can get a very similar configuration for £1,500 compared to the HP's £1,600. You'll get 4GB of RAM, a 500GB, 7,200rpm hard drive, HD webcam, Blu-ray drive, backlit keyboard and aluminium lid. Connectivity will also be very similar, and the Nvidia GT 550M graphics should give roughly comparable performance. However, not only do you pay £100 less and gain more flexibility, but you also get a newer Sandy Bridge Core i7 2620M CPU, which should give both faster processing and better battery life, especially with Nvidia's graphics-switching Optimus thrown in.
HP's premium Envy 17 3D oozes class, is stuffed to the brim with features and connectivity, and offers powerful specifications. It includes a stylish metal-clad body, an impressive Full HD, 120Hz screen and accomplished 2.1 speakers, and with its comfortable 3D glasses provides one of the better mobile 3D experiences going. However, you pay a considerable premium for the same basic specifications that others better for less, so it's not the best offer around.