Electronics for JM Lab Grade Utopia Be

Looking for advice on amplifiers worth listening with JM Lab Grande Utopia Be in a medium sized room (50 square meters, 450 square feet).
Music taste : mainly classical (including Mahler and Shostakovitch symphonies) , jazz and vocal.
Gryphon Antileon Signature or the mono blocks. I'm using a Gryphon Antileon with the JM Lab Nova Utopia and best match I've had so far.
Our customers report that our MA-2s are a good match for that speaker- it seems well suited for tube amplifiers in general, but seems to like having some power. 200 watts seems to be a good amount of power for a room that size.
My friend uses a Pass Labs X350 on his Grande Utopia and the result is very good