Btw, I will probably audition the Danley SH50 any day now. That's another highly regarded horn construction. I've asked Bjørn for an audition of his system, but he's a busy man. But hopefully I'll be able to hear it in the not too distant future.
I had a pair of Klipsch K-402 for several years. They were sold quickly when we developed our own horn. The difference was bigger then I expected. Smoother, more relaxed, more natural sound with more energy in the highest frequencies. The off-axis measurement was improved. A large horn system with constant directivity is amazing IMO.