I bought this amp as an upgrade to my home studio setup. I'd been using a Blackstar HT-5 for about 8 years as a home practice and recording amp, and wanted something with more variety and better headroom, particularly on the clean channel. I opted for the Harley Benton G112 cab offered by Thomann - note that there are certainly more expensive cabinets out there, including the intended PRS 1x12, but as the Harley includes a Celestion V30, this was more than sufficient for my needs.
My signal chain is: PRS SE Santana (2011) -> Exotic EP Booster -> Maxon OD808 -> amp. In the effects loop: TC electronics Plethora -> TC electronics Helix -> TC electronics Flashback II (currently running as a looper).
My first impression was with no effects or overdrives/boosts, simply guitar straight into the amp. And this thing did not disappoint! The clean channel is beautiful: clear and chimey, with crisp highs and a wonderful mellow character overall. I was worried that it might sound sterile or lifeless without at least some reverb, but the character of the amp really shines through. Not surprisingly given the 6L6 power section, it's closer to Fender territory than say Marshall or Orange, but remains quite balanced without becoming harsh or shrill. The pull-out boost on the treble knob is also a welcome addition, as the clean channel does retain excellent headroom. With the boost engaged, there's a really gorgeous airiness to the tone, with strummed chords singing and single notes sustaining really clearly. Adding some delay and reverb, the treble boosted sonic palette takes on a wonderful character, becoming rich and resonant - finger picked arpeggios sound remarkably clear and full.
Most people will be interested in the overdrive channel here. Unsurprisingly, this is really outstanding. There is an enormous amount of gain on tap, although even with the gain at max, the tone remains very usable; chords retain definition and leads sound smooth and full, without sounding grainy or harsh. My own preference is to keep the gain relatively low, typically below half way (although note that this is still quite a lot of gain!), and to then add extra punch with the Exotic and midrange with the Maxon. I'm not really a metal player, but for saturated leads (ala Gary Moore, Satch, etc.) this amp is incredible. If I had one complaint, it's that the lead channel does attract some noise, even with the gain at moderate levels - not surprising, given the number of gain stages here. I usually keep a Sentry Noise Gate within my pedalboards on the Plethora, and this deals well with any extraneous hum.
My only other complaint is not having had enough time yet to play with this amp! I also considered the Hughes & Kettner Tubemeister 18 when buying the MT15. That had the added advantage of the Redbox DI, something lacking from the MT15. However, the difference in price between the two amps on Thomann is roughly the same as buying the Redbox alone, so that's always an option.
Overall, I highly recommend the MT15. I haven't gigged with it (unlikely to in the near future, given the Covid 19 situation across Europe). I can't imagine that it would struggle to keep up with a drummer; even at 7W half power, it's remarkably loud. You will not regret buying one of these!