I didn't want to buy this receiver, since I was very happy with my Sony STR-DA555ES. The growth in HDMI sources forced me to reconsider, and I bought one for its HDMI switching ability, with a little trepidation as to whether the sound quality would disappoint. I needn't have worried. This receiver is both powerful and musical, (and even a little smaller and lighter than the previous one). I use it in a "4.1" configuration, i.e. front and rear left/right, plus a subwoofer. Much of my usage is for music (SACD). The quality is excellent in all regards.
SKY HD uses an HDMI input, unfortunately not for sound due to some odd thinking on SKY's part, so the audio is input via optical. The receiver ties these together as a single source, (named SAT). Another reviewer has mentioned a video/audio sync problem, and I sometimes see it on this source only. It changes with SKY channel, however, so I'm more inclined to blame the source.
For DVD recording I use a Sony RDR-HXD910 HDD/DVD recorder which does its own upscaling, connecting via HDMI.
The third HDMI input is occupied by a Popcorn Hour A-100 media player, used mainly for high definition (1080p) video, both from a Sony HD camcorder and slideshows created on a PC.
The fourth HDMI input is for a blu-ray player. Having been very pleased with this item, I eagerly looked for a SONY blu-ray player that would also play SACD, DVD, DVD-Audio and CD. There isn't one. Instead I have obtained an Oppo BDP-83 which does all of the above and more, and very well. It uses all of the generous capabilities of the receiver to fine effect. Unfortunately the receiver does not handle DSD on the HDMI input (from SACD), only PCM which is audibly inferior and also available from the Oppo, so instead for SACD only I use the multi-channel input which handles the Oppo's analogue outputs extremely well.
Stereo audio from my TV is fed into an analogue input.
In conclusion, the receiver handles everything I have thrown at it with aplomb, and is equally capable of room-shaking movie sountracks and delicate classical music. Video switched via HDMI is indistinguishable from that fed directly into the TV, and standard definition analogue inputs are noticeably improved by upscaling. I have two minor complaints; firstly I feel a DAB radio tuner in addition to the fine FM one should have been a feature. Secondly, I have VERY occasionally had distorted video output (blocky digital artefacts) when switching from an audio-only source to one with video. This is always cleared by switching to standby and on again, taking less than 10 seconds.
In conclusion this is a fine piece of equipment, well worth its cost.