Hmmm. Just looked on AFF. £15 a month to be able to even see someone's profile? I won't be doing that any time soon. If you could see the profiles with a free account I may have been tempted to sign up if there were a few worth contacting, but there's no way I'm paying that just to get started.
From experience: I've used AFF a few times over about a decade, and had some good quality meets initially. Including one where I thought I might have been shagged into an early but very happy grave, by a slightly loopy but very attractive, slim 6' blonde, who insisted on taking me back to hers after a pizza. Completely redefined for me the definition of rampant sex. That was a night I'm not likely to ever forget - it'd probably kill me now!
But back to reality: The last time I signed up for AFF it was more than pointless, infact the polar opposite of what it was originally. It cost me time and money with zero results. They had resorted to using a method I've seen in numerous other sites, where you get spammed with hundreds of bot-generated messages from presumably false accounts based all over the world, from people you'd not touch with Ann Widdecombe's. It had gone downhill, and badly.
Similarly with Sh*g Find.
From my own experience, I'd just avoid these sites. They have massive advertising spend to drag in thousands of (male) customers each day and spend it on still more advertising. Keep your inbox manageable and keep your money and valuable time for something that actually works would be my advice. SA sounds like it's become what AFF used to be (ie: good and productive), though I've not signed up for it, yet.