in my opinion, wide moves make f2l not as smooth. rotating doesn't take that long anyway, and sometimes rotating can help with lookahead, since you get to see the rest of the cube. And yes, knowing what pieces are affected, and knowing where they will end up, can make this insert pretty good. however I feel that it is harder to learn this because of the wide moves, compared to R U L moves. and most top cubers prefer not to use inserts like these. but I do think that it is ok to learn this, once your decently fast. but if your in the process of learning f2l, getting basic efficiency, working on fingertricks, starting to learn how to lookahead, or you already know how to lookahead, but your not that confident. then you should learn this another day. so I think if your going to learn something like this, you should be averaging like 10 and under. since you should have a lot of your basics down by then, however you could learn this when your a little slower, depending on which parts of your solves are faster/slower. but to be honest, its all personal preference, and if you really want to learn this, then you definitely should, because if your not having fun, your not improving.