mbl or levinson for wilson sophia

I own a pair of Sophias. My preamp is the ML 380 and power amp is the ML 431. While this sound is pleasing to me, I think I can do better and trade up my preamp. I will be auditioning the VTL 6.5 and other tube preamps. I've heard the Spectral pre and power amps and wasn't impressed. I've heard Krell amps and wasn't impressed either. I think the Sophias are very revealing and SS equipment might not be suited for it. If I were in your shoes I would audition tubes vs. ss amps and then decide what make to go with. Tubes will give you a bigger sound stage although the ML 431 is big too, that's why I bought it. But maybe a tube amp will make the Sophias sound smoother.

Why not ARC Ref 210 ? ARC was demoing their new 210 monos with Sophias during CES2006 and the combination was very good.

Wilson has always been partial to ML and for a long time Dave Wilson voiced his new product with ML. He also used ML in his home system. The Sophias present an easy load to the amp. I am not familiar with mbl's claim to fame but do know you won't go wrong with ml.

I really enjoy my 436s. I think they'd sound great with Sophias. I have not heard mbl so cannot comment.

What about VAC. The PHI stuff is sensational.