Amp for Revel Ultima Studio 2s


I currently am driving my Revel Studio 2s with a Simaudio Moon Evolution i-7 integrated but am looking to move to a more powerful pre/power amp combination. I only have room for a stereo amp (I don't have room for 2 monoblock amps). My audio cabinet (recently custom made) can also only accommodate an amp 20" or less in depth and 9.5" in height (although less height is ideally needed for the amp to breathe - the space in the cabinet is only 10" high).

I'm considering moving up in the Simaudio line to a P7 or P8 pre-amp plus a W8 amp. Other option is McIntosh MC452 amp and a Mac pre-amp or Mark Levinson 532H amp and a ML pre-amp (or a mix of the Mac/ML gear). Suggestions?
camb
Is it best to stick with one manufacturer for the pre amp and power amp (eg. Simaudio P-8 pre amp and W-8 amp) or can I get better results by mixing a tube pre amp with a solid state amp (eg. Audio Research Reference 3 pre amp and Simaudio W-8 amp)?

thanks for you comments!
Theres a heck of a good deal on a Supratek Chardonnay in the classified.Im a bit biased as I love mine!
I use a Levinson #431 with my Salons with good results , but the Simaudio / Revel mix seems to be a match made in heaven , the W8 or W7 would be my choice .