I tried using the #2 for a show last year for a Lachy Doley recording with my ADK A51s. It was completely blown. I chalked it up to a mismatch with the sensitivity of the mics although I'd never had an issue running them with any other preamps.
Possible anecdotal confirmation-
I only ran a borrowed Aerco a couple times about 15 years back to give it a try with some on-stage recordings. Both times the resulting recording was "completely blown / distorted". I think I was running ADK TLs thru it (goodcooker's post sparked my memory of this), but might have been Gefells. I also never had that problem with those mics through other preamps. At the time I chalked it up to something wrong in the Areco. The owner (Spyder9) sent it back to Jerry to check out, but I'm unsure if he determined that anything needed to be done to it or not.
The one I've had for years and ran many times with mics of similar sensitivity to the ADK a51s (15mV/Pa - I often ran mk41s with it 14mV/Pa and MBHO KA300s 12mV/PA) never had any issues beyond the odd slightly distorted transient peak now and then at a really loud show.
The one I had the problem with last outing was the one I got from Darby. I have a suspicion that this one is made with the higher gain structure for nature recording. It was a loud show that came out distorted but not crazy loud. It was a smallish club with a hanging line array and I was 40 feet from stage in my usual FOH cage spot.
I initially thought they had different transformer models in them but I was confusing manufacturing lot numbers with model numbers - they both have model JT - MB - CPCA. The older lot number has the printing directly on the top of the can. The newer lot number has the printing on a white sticker on top of the can. They should be the same.