Time for a new amplifier for my Dali Euphonia MS4's - here are the options. . .

In my budget now on Audiogon is a wide variety of options, in no particular order:

Bel Canto Ref 1000 mkii monobolocks
YBA Passion A650
Valvet A4-CB monoblocks

If I break the budget there is an Aesthetix Atlas Sig up for grabs,

None of these are available for me to hear, so any experience you have with any of these combos would be appreciated.  Thanks in advance.
I ran the MS4 and MS5 with Pass X250.5    highly recommended
 Im running my MS4 with a Simaudio W5.3SE. Love it.
To jswarncke....

As the new US Distributor for YBA, we're glad to see you are consider YBA's Passion A650.

I'd also like to suggest the Genesis series A6 amplifier - based on the Passion series using Yves-Bernard's extraordinary circuit design but slightly less power output and lower cost.

Good luck in your search!