I also have Boston VR 2's and love them. But I have heard bookshelfs that sounded good. I've also heard bookshelfs that sucked. John Garcia has some of the best bookshelfs I've ever heard, (they are custom-made DIY's though). It seems that as long as you get a good bookshelf that will play low enough, and integrate them with a good sub, they can be just as good as a tower.
In fact, when I bought my VR 2's, I was actually planning on buying bookshelfs to save space. But the manager at Magnolia kind of talked me out of it. Once you put a bookshelf speaker on a stand, you pretty much have the same footprint as a tower, so you're not really saving much space.