Well I've had my VSX-84TXSi for a little over a week now so I thought I'd post a few thoughts.
This unit is replacing a Denon 4306.
Why replace the 4306 you ask? Mainly because Audyssey wasn't doing it for me. And you just can't have enough HDMI inputs (4306 - 3HDMIs, 84 - 4HDMIs). Also THX certification, 84 has it, 4306 doesn't, not a big deal granted, but nice to have.
But probably the main reason.... I've always liked Pioneer's MCACC room EQ system. Combined with my Velodyne SMS-1 for subwoofer/LFE EQ'g, the combination gives me the best overall SQ that I've heard in my listening room, with my system configuration. Be it two channel music, HT, or high-rez multichannel music, the combination of the 84 via iLink from the DVV-79AVi dvd player, MCACC applied, is... well (remember the line from Sleepless in Seattle) MAGIC! Not really magic of course but it works for me.
My speaker system is the NHT Evolution M6's front and center, NHT L5's side and rear surrounds, with a SVS PB12-Ultra/2 subwoofer.
Anyway the 84's HDMI inputs work flawlessly with all my sources (DV79AVi, Directv HD Tivo, Toshiba HD-XA1 and the OPPO 970HD which is pretty cool with it's PCM transfer of SACD, etc... via HDMI, one cable carries everything and while it doesn't sound quite as good as iLink via the 79AVi, it's still very doable).
I was hoping to feed the 84's video processor 480i via HDMI from both the 79AVi and OPPO 970HD, have the 84 process to 720p or 1080i, but that's a no go. 84 just passes 480i via HDMI along to the display with no processing whatsoever.
To make a long story a little bit longer, while I've only had the 84 about a week, I'm very pleased thus far and it hasn't done anything to make me think, "this is a nice unit... but".
No buts at this time.........
geoh