No doubt Vandersteen makes great stuff, and they have been for a long time. They sold over 200,000 2c's for a reason! Also with the 3a being around so long, essentially unchanged, you can find really good deals on them used from time to time. If you found a pair for $1500, it would be pretty hard for us to compete with that.
That said, although a well executed design, it is a dated design with dated drivers. I'm not personally a fan of that aluminum tweeter, it's best when subdued to where it pretty much disappears sonically. And the midrange/woofer are both well integrated and smooth, but not very resolving or articulate. Overall it's a very easy to listen too speaker, but doesn't exactly take you deep into the recording. The Cirrus will greatly exceed the 3a's resolution and transparency, the 3a can give a bit more bottom end energy. But sub or subs are easy to add and integrate, and a Cirrus with proper sub integration can deliver the kind of sound you'd expect to have to spend $20K to achieve.