I find that I use recs only for fandoms that I'd never have thought to read fic for on my own. For example, I love comms like crack_van and epic_recs, because otherwise I'd never have found some really fantastic but random fic, like one for Kiss Kiss Bang Bang, and an Ugly Betty/Batman Begins crossover that is my favorite thing ever. I almost never listen to recs for fandoms that I already sometimes read; if it's for a character or pairing that I would read, more than likely, I've already read it by the time someone recc'ed it, and not even a rec from my best friend ever would get me to read about a pairing I don't care for. To be honest, when I make rec posts, it's mostly as a way of keeping a log for myself of things that I like, rather than because I expect anyone else would care. The only times I've ever really branched out of the pairings and authors that I already like have been during exchanges or kink memes, when for some reason, I feel much more open than I usually do. I read 75% of the stories at heroes_exchange and plan to read everything I can possibly understand at the crossover exchange.