The original V3 is a great amp. It has its own sound. Just a couple points I think that you need to realize are that the amp is not idiot proof. Many people dial the V3 in based on their pre conceived ideas of how the controls should look when dialing in an amp rather than their ears. This can lead to shit breath tone and thoughts that the amp fails. Many people claim the amp sounds fizzy and I swear that 90% of these claims are from people who have not learned the amp properly. The V3 has not only a treble and presence knob but also the global bright control as well as the expanded eq switch. That is a shit load of high end frequency control. And sometimes people go a little crazy with those things not having previous experience and dial in a crap tone then blame the amp. So if you get one just be fair to it and use your ears, not your eyes.
The only negative to the amp for me is that global control panel. Its a great sound shaping tool but at the same time I hated it. The reason being you couldnt turn it off or assign it to the channels you wanted to use it on. So if you dial in the tone you want on the clean channel its quite possible you wont like those global control settings on the dirty channels. Ive heard people say that that is why you have the presence and treble knobs to fine tune but then that just makes the global controls pointless to begin with. And still thats not true as the controls affect different frequencies. The V3 sounds fantastic, you just need to be patient with it.
as for the V3M, I cant recommend them. Honestly aside from the name and the similar look the amps sound nothing alike. I wanted to love the V3M as it didnt have those pesky globals but the amp has very poor sound. Some amps you struggle to find a bad tone, the V3M is the opposite. I struggled to find a good one. And if your into metal you can forget about it. For a lack of better description the V3M sounds like a fart through a tubescreamer, I shit you not. A good example of the poor tone is Carvins very own demo video with kevin michael from sledd. The ONLY thing that gets that amp to have any definition and clarity is a TS type boost pedal. Without it I would have to rate it in the top 5 worst tube amps for rock and metal in recent years.