I've been tempted to use 11s at times, especially when I've been playing regularly and my fingers then find bending the strings very easy. I do have one guitar set up in open G with 11s on, but it's really for rhythm playing. And of course, quite a few people tune down a whole semitone and use 11s to counter the lower string tension. Useful for doing Thin Lizzy tracks. SRV used to downtune a lot as well.