I have been using Blackout 16 and Red Devil 16 on a Babolat APD GT for half a year now. I string Blackout at 42 lbs main, and Red Devil at 44 lbs cross. Sometimes when I hit all out, i feel it a little in my forearm afterward. But most of the time, I don't ever hit that hard, and I don't feel any pain at all. I can play until the main string breaks, which used to be 12 hours, but now is about 24 hours now that i am driving the balls more than just spinning it. Blackout on the main strings has very good spin, consistency, and tension maintenance, and is soft enough not to hurt my arm. Red Devil on the cross strings provides power, comfort, some ball pocketing, but still has good tension maintenance (probably because the thick 16 gauge is not overly worn by the time the main string breaks). I have a semi-western grip, and it provides plenty of spin to keep the ball in the court. If you are a flatter hitter, you will probably want to string it in the mid to upper 40s pounds tension-wise to keep the ball from flying out of the court. I used to use Vendetta nano 16 in the main strings instead of Blackout 16, and i really liked the slightly more ball pocketing of the Vendetta nano. But the greater control of the Blackout due to its lower power without any tramboline effect from the minimal ball pocketing of the string has made my game even more consistent. Blackout's low power level and lack of ball pocketing makes the ball response very predictable, thus increasing consistency and swing away confidence.
I am seeing that others are liking the combination of Blackout mains and Black Force crosses. Has anyone who has tried both Blackout/Black Force, and Blackout/Red Devil, please compare both. I have heard that Black Force does stretch significantly, so I am wondering if tension maintenance would be decreased compared to Red Devil, with the result being decreased consistency in Black Force compared to Red Devil (when both are used as crosses). Thanks.