I went to a Craft Fair with daughter last weekend - it was packed and the Ladies loo situation with long queues was ridiculous! So as I was standing in this long queue - bursting - I noticed the Gents door to my left and tentatively pushed it open and it was completely deserted. (There were very few men there apart from a few 'tethered and dutiful' husbands and some delightful men manning the stalls doing needlepoint etc.)
Switftly in I went, with the woman in the queue behind me saying "I like your attitude" and "I'll let them know you're in there if need be." I mean for me it's a no brainer - long queue or relief, no contest. That particular loo was clean and not at all smelly and they had lovely handwash at the basins. I've shared my toilet at home with husband and son and a gazillion other males, some of them strangers, over the years. Same with disabled toilets, I'll use those too if there aren't any disabled people needing them at that very moment, and I know I'm going to be quick, and there's no other option!