I took delivery of the 55" model 3 days ago. Since I was upgrading from a 32" CRT (budget Toshiba) some of my observations might be a bit obvious, but here goes. I have not played with the settings very much, so this is how it performs out of the box.
SD performance - the worst SD freeview channels are fuzzy like a cheap VHS recording. At best they are tolerable, but you would not choose it over an HD alternative except that the Teletext facility seems only available in BBC SD.
HD - what a difference! Freeview seems to broadcast in 1080i format which is a great improvement on SD, though some skin tones can still appear a bit plastic on occasion such as brightly lit close-ups compared to the CRT. Detail on static or slow pan images is excellent; cloth and hair textures are a highlight. There is some blurring when tracking motion (e.g. World Cup coverage) compared to the old CRT. Colours are realistic and enjoyable.
DVD - this is superb working in 1080p. Upscaled DVD is beautiful (The Dark Knight) though I am not sure if the TV or the Sony S6200 player was doing the upscaling. Motion in the action scenes is more faithful than HD broadcast. Cannot comment on the depth of blacks or brightness of whites, but nothing stood out as an issue.
Blu-Ray - only watched the Disney animation of the Jungle Book so far which was Cinema clear and bright. The trailers looked okay. I might get back to you when I watch Game of Thrones Series 3. Looking forward to using the THX preset.
Sound - is pretty reasonable for news and casual watching, though this may not be the case for the smaller model. Just had a play with the sound setup and despite it being less than 30cm from the wall, i prefer it on the greater than 30cm setting. The surround setting adds a bit of pleasing ambience. Most of my listening will be through the AV system (Sony STR-1040 and Dali 1 5.1).
Smart - some nice toys. Found the Berlin Philharmonic Digital Concerthall and was blown away by sound on the trailer. Whatever signal is being sent down the ARC to the AV amp, there is no interference from the TV. Not likely to try out Netflix or social media any time soon, though I may have a go at YouTube soon.
Twin screen - never been able to watch broadcasts simultaneously before - 2 World Cup matches side by side (only one with sound thankfully) - a must for sports fans. I need to find out if I can use iPlayer or online broadcasts as one of the views (for use with Formula 1).
Home screen - nice feature - living on my own, I will not use this to its full potential, but I can see the benefits for families.
Challenges - I get sound only from the Virgin cable box. This is a Scart feed from the box to the AV HDMI input on the TV. The HDMI feed from the box is currently going to the AV amp. I would like to use the timer feature for switching channels - the timer feature on the TV appears to be just for recording (can I use an ordinary computer external hard drive for recordings).
Am I happy - yes. Would I recommend it - yes. Is there better out there - for the money, a matter of opinion, but I reckon the picture is hard to beat.
Biggest gripe - having seen it advertised on sale in early April and ordering it in mid-April, I had to wait till mid-June before it arrived (not the fault of Richer Sounds who have been superb, since no other retailer had it either).
If anyone else has an AS802, I would be glad to hear your thoughts.