Help, question about Mcintosh Ma5200 or Ma6700.


I recently auditioned a Mcintosh Ma5200 and really enjoyed the sound. I use B&W CM7s in a small area (where I don't play music loudly). Would anyone have a opinion on the difference in sound of a Mac with more wattage and autoformers (eg. mac6700, ma7900), but played at a relatively low volume.

Thanks for any input!

FYI, I am currently using a Cayin A50t amp.