I think the 2 previous reviewers were spot on for covering the male experience on the site but I thought it would be fair to give a female perspective since there isn't one on here.
If you are a woman looking for NSA/FB encounters AFF will change your life. If you think you want to start off with an NSA and then eventually turn it into a relationship, I don't think this site is for you.
There was a serious learning curve when it came to AFF but here are the pertinent points:
Fill out your profile. Make a list of the 3-5 most important things to you in a FB. Post them. Post sexy photos. Wait, surf profiles, and send messages when you like someone's profile.
Don't respond to the angry hate mail or 2 word/1 sentence emails. If at any point in your communications or profile perusing you get an odd feeling about someone, just disappear. They'll be others, I promise and you'll be saving yourself from a whole lot of crazy. The good ones make themselves known, clearly. Weeding through the chaff takes a lot of time but the rewards, oh the rewards, are so worth it.
The world is generally more accessible to the attractive but moreso on a sex site. I'm an attractive gal but I have never been so visually satisfied with my bedfellows than when I was on that site. Now that I'm regular dating again, it is with a sigh that I relinquish the sight of washboard abs and strong jawlines from a daily basis to a couple times a year occasion... and remind myself that kindness (which was definitely lacking on that site) counts for a heck of a lot more. I was looking a little above my rating on AFF but not leaps and bounds over. Reality should still play some part of your expectations for your AFF finds.
Most of the men I met with exceeded everything I ever thought I'd want in a lover but even they had horror stories of pretty but insane women and women with unreasonable expectations. The site is overrun with pros and webcam girls so the few real girls are in high demand. The attractive real ones can have a ball if they have the fortitude and patience to weed through all the junk and a thick skin to get through the sheer insanity of it all.
Pros
If you are realistic about the female soul sucking nature of NSA relationships and you are still sure you want to do it, you can meet seriously attractive, intelligent, and skilled men.
Allows you to pre-screen a little bit better than with beer goggles on in a bar.
Can be free if you are attractive/in demand.
Cons
Guys don't try to trade up on this site. Otherwise you are going to be very disappointed (If the hotness of the girl matters THAT much to you, hire a pro. If a woman wouldn't go out on a normal date with you why on earth would she be willing to have an NSA arrangement with you, for free?) Ladies, don't try to trade up too high, either. The world unfortunately still revolves around youth and beauty, free sex or no.
I don't think anyone besides a hard core sex addict could survive on that site for long. For a woman, it is difficult to remind yourself that ultimately your feelings don't matter. It is only ever about sex.
The site blocks and loses messages all the time. Repeated attempts to trade email addresses can be frustrating, but if they are that hot, keep trying.
Be wary of autorenew. I swore I turned off the auto renew feature more than once and I got renewed for 2 subscription rounds anyway. By the 3rd, it stuck and I was able to shift back down to a free account.