Like you Cayugad, I could easily shoot enough shots in an afternoon's shooting session to use up most of a canister of Blackhorn. So price is my main and only real issue with the stuff.
In my Omega X7 with 250 grain Deep Curls I get about the same velocity and accuracy with charges of 80 grains Blackhorn or 95 grains GOEX FFFg. With those loads I get about the same number of shots from ten ounces of BH as I get from a pound of GOEX. Yet the BH costs over twice as much.
So the only issue I've ever had with BH is cost. I firmly believe that it's a rip off - even at $27 a canister. My favorite comparison is that IMR came out with Trail Boss powder for cowboy action shooters a year or two before Hodgdon came out with Blackhorn. A canister of Trail Boss runs about $12. I wonder what the real mark up is on Blackhorn?
As for other factors, no swabbing with BH is nice. But swabbing has never been a big issue for me. Barrel clean up with either powder is about the same using pure alcohol for BH and water for GOEX, but breech plug clean up with GOEX is a little easier. Not enough to get excited about though.
All in all, I don't shoot my inlines nearly as much as my sidelocks. So using BH in the X7 and Mustang isn't going to break me. But DANG IT, I still feel like I'm being ripped off every time I pull the trigger with it. But then, I feel like I'm being ripped off every time I pay my cable bill also.