Which is better?

Heard some Luxman products this week along with several other brands and different pieces of equipment (streamers, Dacs, preamps, speakers, amps) and was very impressed with Luxman's neutrality and am considering a couple Luxman components.  First time I have had the chance to hear this many multiple brands of electronics and speakers in multiple different combinations.  First, I'm inquiring to see what people think about the following:  Would you purchase 2 x M700u amps (120 watts per channel each) to be used as mono blocks or 1 x M900u amp (150 watts per channel).  Potentially looking to move away from current McIntosh mono blocks.  Current speakers are Martin Logan ESL15a's which are obviously power hungry.   Would also be purchasing the C900u preamp to match with the Luxman amp as that was also the preamp I liked best. I preferred the ss sound over the tube.  I don't have a preamp as I am getting more into a 2 channel set up. I have been using my McIntosh MX160 home theater as both.  After hearing many brands Luxman is what I found to be the best sounding electronics to me.