Opinions on Various McCormack amps

@nickwin   If I were you I would just call SMc Audio and talk to Steve McCormack.  He's a very nice guy to talk to and should be able to supply you with accurate information.  Their # is 760-732-0352.

Good Luck!

+1 hifiman- Steve is very approachable and you can count on him to give you accurate recommendations if you give him specific information. 

@nickwin- The .5 and 1 w A level revisions from SMc Audio are substantial improvements over the 125/225 stock amps. 

Thanks for chiming in on that swampwalker!  I suspected the revised amps to be superior to the production units as Steve had explained the limitations he was under with the production units to hit specific price points.  I believe, that was in large part, one of the key reasons Steve started SMc Audio.  He really wanted the opportunity to put out statement pieces.  I have had my Rev. A+ for years and I still absolutely love it.  It has no discernible sonic flaws that I've been able to perceive.

I have an amp with Steve now getting modded. I have several of his modified amps... Including monoblock conversion, balanced inputs, etc.

One of mine is a Rev A Platinum, but he really doesn't categorize mods like that anymore. It's more customized per person instead of a blanket list per category.

In fact, the amp he has now is one that I had him mod a couple years ago that was even more advanced than my Rev A Platinum.  Things have changed so much in a couple years that he is adding some stuff and a totally new mod he is trying on my amp.

The reason I highly endorse his products is not only related to his great customer service and performance, but selfishly you save tons of money. You literally never have to pay dealer markup again.  I originally bought my first DNA .5 over 20 years ago and it's still in service and always remains state-of-the-art and practically brand new with these mods. 

At current day dealer retail pricing, I have close to a $20k amp (assuming just reasonable markup) at a fraction of the cost.  With crazy markup you see in other brands, it's an even bigger bargain. 

For example, if you really want a pure silver transformer like the ones Audio Note charges $100k, I know he's done them on monoblocks at a fraction of that cost (still pricey though).

People are starting to catch on though. I used to see stock dna.5 amps go for $400-500.  Now they are actually increasing in price.  I guess demand has picked up for these quality stock amps that can be modded to world class.

The only drawback I can mention (actually a positive depending on your perspective) is that he's got quite backlog of work, so expect to wait about a month or two for mods to be done.

To answer OP's last question, years ago I asked Steve a similar question and he said the DNA 125/225 were roughly on par with his B revisions of the older units.  So that would make the Rev A amps a sizeable step up from the stock 125/225.

Might be worth asking Steve if modding your amp might make more sense than buying another stereo amp?  Just a thought.