ayre mx-r versus audio research ref150

have a set of vandy 5a's. running mcintosh (had prior to vandy purchase) tubes. don't like dry or bright sound in any way. also like a solid lower end - thus the vandy's. like liquid and relaxing but not syrupy and slow.

any advice on sound differences between mxr and ref 150 with either a audio research ref5 or kxr pre?

thx