Hmmm... the PM system seems to have changed.
In my experience there is little to no difference in Blu-Ray picture quality between players. It is not like DVD where interlaced video must be processed to display correctly on an HDTV. If a player cannot get the 1080p video on a Blu-Ray disc output to your TV and do it 100% perfectly then it's not qualified to be a Blu-Ray player.
The only area where they really differ is DVD upscaling. Some are definitely better than others. The Panasonic players, while excellent at Blu-Ray, are so-so DVD upscalers. With that said, Panasonic is my favorite Blu-Ray player at this time. One thing that really bugs me is the fact that so many Blu-Ray players are extremely slow taking over 1.5 minutes to turn on and very sluggish to respond to remote commands. The Panasonic players are as speedy as your average DVD player.
I have not seen the Sony BDP-S350 but the S300 has to be one of the slowest Blu-Ray players available. I can only hope they sped up the S350. It appears that with the S350 they have fixed at least one glaring issue with the S300. The S300 does not support any of the high resolution audio formats. The S350 can bitstream all of them which means you would be able to take advantage of them. Your 3808 can decode the high resolution audio formats.
The fact remains, however, that the PS3 is really the best Blu-Ray player on the market. It is the fastest, supports all of the audio formats, and has excellent upscaling capability. The biggest drawback is that it does not have an infrared remote without buying a separate adapter and it is noisy.
If I were to buy a Blu-Ray player today it would probably be the Panasonic BD-50. I don't want a PS3 and I much prefer a standalone player. Also, since my Yamaha RX-V2700 does not have decoders for high resolution audio I need the player to do that. The Panasonic is the only one I know of other than the PS3 that will do all of them. In your situation I would wait for the BDP-S350 and try it out yourself. I would also look into the Panasonic BD-30. It is out now and is available for around $400. It can bitsream all audio formats. The only drawback is the fact that is only has average DVD upscaling.