Anyone compared Audio Research Ref 75 with Ref 250

Hi, I am planning to upgrade my my amp from ayre v1xe to either ref 75 or ref 250. Looking for suggestions.

Here is my system

Vandersteen 5A
Audio research ref 5se preamp
Audio research dac8
Bryston bdp-1 music server
Hmmm ... no comments. What did you decide to do?
I bought Ref 250 and very Happy with it. Thinking of downgrading to 75 as I don't need much power with my Vandersteen 5As
Is Ref 150 the best compromise?