Chicago
My girl Vivian Hetaira and I will be visiting Chicago the 10th-12th. We have a big 'ol bag of fun toys with us and nothing makes up happier than to have a nice long time to play with someone. Let us be your first menage a trois and I promise we can show you a thing or two 
Pleasure
Most guys prefer them. With the way they work, they put most of the friction and slide back on the guy's side, where it belongs. (Women are built more for fullness and pressure, not heavy amounts of friction-if you don't believe me, look at the way an uncircumcised cock functions. 
) Female Condoms are so valued by most guys, that TER made it a feature part of a lady's TER profile. I'd say that speaks pretty well to the demand, wouldn't you?
They are at least equally as safe, when used correctly. My personal feeling, however, is that they are very possibly even safer. The material is not latex, and even in "non-latex allergic" folks can sometimes cause irritation of mucous tissues. Irritated/inflamed tissue isn't quite as successful at being a barrier to diseases, thus increasing risk of infection. Also, going back to the issue of the Female Condom putting the friction on the guy's side, that also means her bits-which can develop micro tears due to heavy friction-are better kept intact. Same deal-undamaged tissue-less disease spread. Being made of something other than latex also means that oils present (like from a massage) won't damage the condom, and you can even enjoy natural lubes like coconut oil that won't damage the microbiome of either party. (Basically the bugs that live on and in us, including in our naughty bits, that we've co-evolved with and do all sorts of important things.) Clinical studies have shown over and over that STD infection of any type is FAR more likely to happen when the person's genital microbiome is out of whack. So...using a condom that opens doors to healthier lube options can decrease STD risks. And, regardless of what lube she is using, a Female Condom keeps most of it out of her, keeping her microbiome a lot healthier regardless. Healthier girl = healthier guy (not to mention more appetizing girl bits
). Finally, the Female Condom provides a bit more coverage, which could potentially decrease risk of skin related disease. (That's a big maybe, though, and not clinically studied.)