Thanks very much for an informative review.Funny you mentioned that amp...I had it at my house a couple of days ago.
Very cool sounds...the options are a bit confusing at first, with the reductive master vol and bump feature, but it sounded great.
I was listening to it alongside my 65 fndr twin and suhr od-50 classic.
The monterrey had a nice clean sound with all the bump and master stuff turned off...sort of fenderish but the top end had a vox-like peak to the upper mids and trebles...I guess because it's an EF86 front-end. The tone control is very responsive though.
Once you engage the bump you can beef up the mids quite a bit via the rotary switch that contours the input stage I guess. You can footswitch the bump switch.
To get it to overdrive, you engage the master volume switch, which adds a master vol to the circuit, so you can get saturated tone at lower volume. Definitely leaning more toward the vintage overdrive tones, not really modern distortions. think cranked plexi-ish tone. Still had a bit of vox character too.
It also has a half power option, which is obviously quieter, pretty handy too.
Definitely an impressive amp, but a bit complicated at first.