with the vanalstine I'm not worried about power as much as I am quality of sound. compare with an upgraded McCormack for instance, or a standard McCormack 225.
I have not heard the McCormack amps but I did have an enjoyable afternoon with the AVA 600R in my system driving my Salk HT2-TL speakers. My regular amp is the Van Alstine Synergy 450, since the HT2-TL is an easier load I didn't notice any difference with the power, both amps had plenty to spare. The 600R was perhaps a little more detailed, a smidge less warm but that was about it.
I mention the comparison because I have compared the Synergy 450 to a factory refurbished Krell FPB 200, an NCore NC400 (class D), an Adcom GFA5400, and an older AVA Insight Double Die 450. The Synergy 450 killed the Adcom, Insight and NCore NC400 with the NCore demo spanning a couple of months and a over a dozen audiophiles all agreeing the Synergy is better. The Krell comparison was with the Magnepan 3.7 and the Synergy 450 held it's own, I think the Krell pulled ahead because all 200 watts is class A but that amp put out a lot of heat, it was always too hot to touch. The McCormack amps are getting long in the tooth and are about the same age as the old Krell, at this point I would go for new.
A couple of week ago our audiophile group listened to the latest Mivera Purepower SE with the newest Icepower class D module - I'm keeping the Synergy, just not a class D fan.
A friend recently asked if I'm upgrading to the new Van Alstine Vision SET 400 amp but every time I listen I think 'hot damn this sounds good' (channeling my Grandfather) so I'm in no hurry, maybe AVA will have another 10% off Summer Sale (Frank are you listening?).
Quality wise Van Alstine amps are just as good or better as any reasonably priced amp. A member of our audiophile group just got a PS Audio BHK 250 ($7499) I'm interested in hearing but the price is way above my pay grade.