I suggest a used Ref 150 or 150SE. IMHO both will outperform the Ref 210s in virtually all areas except dimensionality in which monos always beat stereo and perhaps (not really sure) ultimate power if you play at 100dbs which I never do. I had the Ref 210s in house against the Ref 110s and the 210s were perhaps 10% better in only one or two aspects that matter to most listeners at normal or even fairly loud (say, 95 dbs) listening.
The biggest improvement over the 110s by far was in stage width and depth----again---perhaps 10%. But since ARC is famous for that very characteristic, among others, I felt I had enough with the Ref 110 and went with it at the time due to the cost/value relationship.
Having since moved on to the Ref 150 and then adding KT 150s a year later, I can say without qualification that the Ref 150 and 150SE downright smoke the Ref 110 and 210 monos. The difference being more in the range of 25% or more precision, transparency, palpability, texture..I could go on and on. I would go so far as to say that it is my favorite ARC component of all time---and I've had a few. In comparison the Ref 210s lack drive and are a but whispery in their presentation.
Read the reviews of the Ref 150 when it came out and you will be able to glean from the reviews this same conclusion re the latest generation of ARC amps being far superior in most important aspects relative to the prior generation.
The biggest improvement over the 110s by far was in stage width and depth----again---perhaps 10%. But since ARC is famous for that very characteristic, among others, I felt I had enough with the Ref 110 and went with it at the time due to the cost/value relationship.
Having since moved on to the Ref 150 and then adding KT 150s a year later, I can say without qualification that the Ref 150 and 150SE downright smoke the Ref 110 and 210 monos. The difference being more in the range of 25% or more precision, transparency, palpability, texture..I could go on and on. I would go so far as to say that it is my favorite ARC component of all time---and I've had a few. In comparison the Ref 210s lack drive and are a but whispery in their presentation.
Read the reviews of the Ref 150 when it came out and you will be able to glean from the reviews this same conclusion re the latest generation of ARC amps being far superior in most important aspects relative to the prior generation.