I posted a very similar review(?) on another website as user feedback (techradar).
I've been waiting for a HD PVR for ages. Finally the local Richer Sounds had one in stock, so I immediately bought one last nigh (1-Jun-10). First impressions are utter disappointment.
I have had a TiVo for years (now no longer useful since the analogue switch over), a Humax 9300T (I rate 7/10 only due to clunky graphics), and a Sky HD+ (I rate 9/10 with the new shiny user interface). I rate the Philips HDT8520 only at 3/10, perhaps give it an extra mark since it is HD.
I'm so used to the Humax that all the features I really like, appear to be missing from the Philips.
I don't like the program guide at all. Scrolling is jerky. There is no page up/down. When at channel 99 (Babestation

you can't just roll over to BBC1, but you have to press the up/down key for every channel to get back to channel 1. You can't switch to another channel (only start record or series link), instead you have to exit and use a different list (still no page up/down).
My biggest gripe is when in the program guide you lose picture and sound. Both Sky HD+ and Humax when in live, chase play or viewing a recording allow you to continue to view the program while using the program guide.
More subjectively, the program guide just looks amateurish (IMHO), with no good use of colour (e.g. to highligh HD programs - like the Sky HD+ box does). Oh - if the program or channel name doesn't fit it wobbles drunkenly backwards and forwards, even though the full program name is shown at the bottom. Yuk. Who on earth gave the OK for this software???
No search function as far as I can tell.
No manual tune (to avoid getting weak multiplexes).
The one good feature - teletext is more responsive than my Humax or Samsung TV (perhaps the data is cached?).
I'll use it to record HD, but finding the program to record will be a bit of a pain. Looks like it has been rushed out with incomplete software to get it on the shelves before the world cup.
I suggest - try before you buy (if you can find somewhere setup to do this).
I'll probably buy the Humax when it comes out, assuming that it will have all the features of the 9300T.
Having said that the Freesat Humax/Foxsat box also doesn't have picture and sound when in the program guide (unless this has been fixed with a software update) [I gave the box to my sister some months ago]. At least the graphics and program guide looked professional.
--Badsector