I'm late to the party but I will say that I have been nothing but satisfied with my regular subway over the past few months, which was purchased new and in person from Beau Monde guitars, an excellent local shop. The subway has yet to run out of headroom on a gig, it's extremely portable, and it sounds great. The eq is very musical, and it seems as if I can't get a bad sound out of it. The gain staging also does a terrific job emulating the feel of a tube amp.
The plus is cool, but I would have stuck with the original even if given the option at the same price. I have more than enough tone shaping as it is with my passive jazz, my darkglass b7k, and the subway which is usually set with everything at noon. Also, the smaller the better in my book, though the plus looks very convenient as well.
I look forward to further mesa releases. The subway certainly wasn't the first small form class d amp design but it sure comes close to perfecting it! Hopefully one day I'll be able to pair it with some light weight mesa cabs. For now my powerhouse 410 and light weight genz 115 will suffice, and I'm 100% content with that.