If you're looking at the original Blue Heron I'd proceed with caution. While they sound great the chink in the armor is the tweeter. Audax stopped production on that tweeter years ago and used/NOS pairs are very hard to find and very expensive when you do find them. Add to that a high failure rate on the tweeter (pressurized gas tweeter prone to deflating) and you're looking for trouble! And comparing this model ($8,800 new) with the Vandy 5A isn't exactly fair. I personally would only buy them at a fire sale price and do a little DIY to put some other tweeter in when/if they originals fail.
Now the Blue Heron 2 is another story altogether.