This is a holy grail of strings for me. It's awesome! Not too harsh, very playable, great tension maintenance and incredible price. Seriously what is not to like?
I did drop my tension from 62 down to 60 and I just love this stuff. I've been using it for just over 2 months now.
For comparison sake, the past couple of years I had used/tried the following polys: Pacific Polyforce (also excellent), Klip K-Boom, TF Blackcode & Pro Hurricane Tour. To me Black Magic is the best of the bunch.
I tried the Spin X and was not as wild about it.
I'm a 4.5 player & used the string on both my MG Rad Pro and a PST GT.