Great Versatile Amp
I have this amp and the matching HT412VA Cabinet to go with it. It's an excellent sousing amp for clean, crunch, and can be pushed to give you enough gain to play metal/death metal. Some have commented that it has enough gain to replace a Peavey 6505 for metal and I would have to disagree with that. On its own, the OD channel does not have enough gain to play death metal. Classic Metal from the 80's, most likely, but you will not get enough to play Cannibal Corpse or other very heavy music like Slipknot and what have you.
I changed out the tubes for a set of JJ EL34 power tubes and a set of Tung-Sol High Gain pre-amp tubes and it was a huge improvement for rock/metal but the clean still sounds amazing. The JJ's gave it a nice bottom end and the Tung-Sol's gave it a bit more distortion but this tube set still maintained the dark sound this amp has. That is my favorite part of this amp... the dark sound it has when playing high gain/distortion. It's almost like a Marshall, but I like it better. When I play metal I run the master volume full blast and then keep the pre-amp volume low so as not to blow my ears out. This is somewhat the opposite of what a typical metal sound is but it works on this amp.
For the metal sound I set the Gain at 100%, use the American voice setting (there is a button) and that combined with a Tube Screamer with the Drive at 75%, Tone 50%, and Volume 50%. It does lack a bit of that certain tube amp sounds I get from my Peavey 6505+ which I suspect is due to it being in part solid state, but it's got it's own tone and I do love it and so has anyone else who has heard it at my house.
One odd thing is that when I run my EH Metal Muff into the gain channel, I get a ridiculous amount of noise, like it doesn't like the signal or something. I also suspect this is because of the partly solid state design of this amp for the gain channel. If I run the Metal Muff into the clean channel and run the power section full blast ti sounds awesome, but it just doesn't jive with the OD channel. Of these two options though, I much prefer the OD channel with the overdrive pedal set as described above.
As for the construction, it is solid. The switches, pots, handle, jacks, everything feels top notch and I am certain I will have this amp till I am old and gray. The foot switch works great as well. It has a reverb that I think sounds very nice and even has two different voice settings. It's whisper quite when not being played; no hum or squeal or other obnoxious noises some other amps produce (the issue with the gain channel and a distortion pedal aside.)
I recommend this amp. It's got an amazing tone to it and with some slight tweaking can play metal, so to have an amp with some of the best cleans I've heard and have the ability to get a very suitable death metal tone and be built to last on top of that makes this amp a very special thing. The 50 watts is just right, it can sound good at bedroom levels but can easily be cranked enough to play with a band.
One thing I don't recommend is the cabinet. It is a particle board construction with Celestion seventy/80's. Now, it is built very well like all Blackstar products, but you can get another brand cab made of ply wood loaded with Vintage 30's for the same price. If you want a matching half stack than the cab is not a bad purchase, but at that price I think you can get something better. I bought the half stack because I got an amazing deal and I don't regret it one bit.