ARC ref 210 vs ref 150

I've had both in my system for direct comparison. The Ref 210s provided slightly more expansive and deeper soundstage and (my guess is) should provide more power at fairly extreme listening levels.
My test did not go beyond 95 dbs at my listening position.
But in all other respects including grip, palpability and an overall more realistic and natural presentation, the Ref 150 was vastly superior. The slight percentage loss re soundstage was hardly noticeable as that characteristic is provided in spades by all ARC tube amps. Furthermore the low and mid bass was better delineated and more palpable with the Ref 150.
My feeling on ARC gear is that up until the Ref 150/250 series amps, the overall presentation was wonderful and well worth the price of admission, albeit a bit too much on the side of light and airy---diaphanous
I think that problem has been substantially mitigated if not eliminated in the 150/250 series, especially so with KT 120s and now KT 150s.

The Ref 150 is a great amp with original KT 120s or with KT 150s which I installed at Dave Gordon's recommendation prior to introduction of the SE series.
They both sound great, the KT 150s slightly more so IMHO. Not a night and day difference so fear not if you go for an original stock Ref 150.
As to my light and airy comment--this does not relate to warmth and bloom but a bit of steely coolness in the warmth and bloom that the Ref 150 vanquished.
The Ref 150 has tube bloom in spades with a palpability that is simultaneously well rooted in space but holographic--a trick that I have heard from no other amp.
The Ref 150 is the best overall amp (together with the Ref 250) that I have heard in my 20+ years as an audiophile. This comes from someone who has never purchased a solid state amp. I believe it would make a great sound with your speakers which I have heard. I cannot comment on your pre as I have not heard it.
I did prefer my amp over the Ayre monos. In fact the only solid state amps I have heard that I like almost as much as the Ref are the D'Agostinos. In short, I highly recommend the purchase. Of course, if you can listen to it first, that wuld be ideal.

The Ayres were very very good. They were not quite as powerful on the bottom end as the Dags.
But the difference between the Ayres and the ARC was simply the difference between excellent tubes and excellent solid state. Better bloom, 3d presentation and palpable images from ARC. Slightly greater transparency from Ayre. In many other areas, they were virtually indistinguishable.
I am a tube fan. So, for me a great tube presentation beats a great ss presentation.
A ss guy will prefer the Ayres.