Rrog, staying on OPs topic is as simple as saying yes to both questions asked, they are good and they are worth giving a go with the MC30s - that is the answer and the end of the topic. But it would be boring to stop there, and we needn't and you didn't, by introducing the notion of the "next step", which would be to consider a VS subwoofer down the road, and a perfectly reasonable next step, that would certainly improve mid-range clarity and make life alot easier on the MC30s. The question I posed, was (given adequate finances, and a room large enough to give the 3As the space they need) if the next step to really improve upon the 1 would be to sell and trade up to the 3A or add a subwoofer. Not sure what the price differential would be, but the 3A to my ears is a significantly better speaker than the 1, most notably in much more resolved midrange (and of course deeper, more dynamic bass), so if it were my money and I was contemplating my next move, not that the OP is looking that far ahead (yet), I would argue that the 3A Sig is the better next step, IF one chooses to stay on the Vandersteen roadmap, absent financial considerations, or too small a room.
I trust the OP has been given enough encouragement to hook this stuff up, sit back, and enjoy - he is very much into the hi-fi venture with his equipment - and if he is truly a newbie, much better than he knows.