Pass Labs amps questions

SO i started looking into Pass brand amps.  My room is carpeted movie theater of rectangular shape, 18 wide x 26 ft deep.  I'm currently running Audio Research 5SE into Mark Levinson 331 (100 watt RMS SS at 8ohms) then Dynaudio Confidence C4 speakers.  Although I love the sound this gives me, i feel it just doesn't have enough oomph!  For example, in order to sound "right" when i listen to the Eagles Hell Freezes Over DVD, volume is at level 60 on the 5SE.  Im not detecting any clipping at all nor does the Levinson get too warm.  I don't think its straining at all but not sure how to tell.  Its old and i just want to try and get a different or maybe see if i can get a better sound.  I am wondering what the audioafficianados out there would recommend or provide more info on with regards to the Pass Labs line up.  I am specifically wanting a pair of Class A mono blocks.  What falls in my budget is a pair of the XA200.5's on the Agon site here now VS a New/Demo X350.8 demo from Reno Hifi.   Would the X350.8 hold an advantage over the 200 monos with its additional 300 watts of power (C4s are 4 ohms)? I remember needing to double the power in order to move the SPL 3 db???.   If this were correct and given my room size, would this added power benefit my system? All in all would you prefer used pure class A less power or brand new class AB higher power for about the same price?  I'll sit and *listen* for your knowledgeable replies.  Thanks in advance.
chenglo1, the latest  0.8 from pass are more resolving than previous 0.5 and considered by many improvement over 0.5 and they build some better. Even the new furutech binding post are something special. Also you for sure are missing what your speakers can deliver. Plus you have a great pre-amp that many people using with pass. I would work with Mark from Reno HIFI. He will be able to get exactly what you want. Try both class A and class A/AB and see what you like best in your system. Don't just settle on XA 200.5 (even so they are very good). Work with Mark on auditioning newer 0.8 series. His demo policies are terrific. Working with him you be able to get what you like best.
I also agree on a comments about source. if you are using some cheap DVD based source like Oppo, you will not be able to hear what your system can deliver. To match your speaker and pre-amp level you will need a very good source. Esoteric cd players or DACs known to have a great synergy with pass amplification. Latest X series from esoteric are big step forward towards musicality and natural sound.
When I heard the C4 Platinums driven by the XA60.8 monos the needles never moved even though we played at quite loud levels. More powerful than you think.
I strongly recommend that you audition the .8 series before purchasing the .5, just because its Class A.  I recently upgraded from the Int 30A, their Class A integrated, to the Int 60, their Class AB integrated.  Not quite the same as what you are talking about but close enough for me to say that I think you'd be doing yourself a great disservice by not at least trying the .8, even if it is Class AB.  Not quite as sweet sounding, but hands down the better amp in every other respect.  Plus the C4's which I am very close to purchasing and have spent quite a bit of time auditioning really don't need as much power as people seem to think.  So you might want to rethink the power issue as well.
Well fellas, thanks for all your input. I settled on a pair of XA200.5 off our host site here. After reading the reviews out on the web and opinions on the forums, i’m confident it will be a worthwhile investment. Not to mention that it should be a significant improvement over what i am currently running.

With respect to my source, I have a custom built media PC with high end sound card sending signal via SPDIF output using Transparent Reference digital cable to WYRED DAC. Transparent Ref balance cables to AR 5SE, Transparent reference to Levinson 331 and finally MIT Shotgun MA speaker cables to C4’s (haven’t tried Transparent Ref spark cables yet believe it or not-had just upgraded from Transparent Ultra). I used to run a 3500.00 Denon DVD audio player (circa 2005?) but retired it because the sheer advantage of using a media PC that can play my DVD music, HD files, CD’s in WAV format and youtube when guests are over. Yes, poor quality but nice when one is entertaining and someone really really wants to hear his or her song from youtube! However, you have got my attention and perhaps i should invest in an updated CD or DVD player to experience my components full potential. I’m now getting back to familiarizing myself with old music that i used to listen to a lot in my younger days. Preparing my ears for when the XA’s arrive. I’m excited is an understatement!!!