I owned a Blackbird and didn't care for it....sold it. I currently own the Ridgerunner and prefer it immensely. My wife and I own at least seven hammocks and it's by far my most comfortable. The only downside is the slight weight penalty because of the poles but even with that, I will probably take it when I return to the AT this Spring.
As you can see there are a variety of opinions so I would take Brandon's advice and buy both and return one. Better yet....keep both.