Just tried Firestorm in my IG Radical pro at 48/46. Very impressed with this string. I am using Dunlop Black Widow in my backup racquet so in comparison:
Very plush feeling string with excellent ball pocketing and feel. I would say on par with BW if not a little better in the feel department.
Powerful string, but not too much spring even at low tension. I was able to hit out with confidence, very solid " thrack " when hit in the sweet spot. At least as powerful as BW.
Spin was very close to BW even though it is not a shaped string. Serves had very good action, flat serves were noticably harder then BW. Groundies had great action as well.
Comfort on this stuff is second to none. I have not hit with a more comfortable poly, including BW.
Excellent poly in all regards. Really stands out in the feel department, great comfort, and good power. Can't comment on the tension maintainance, only have about 3 hours on it, but so far so good.
Definately worth a try as a full bed poly.