There's a girl that I have really strong feelings for, and she returns them back just as much. However, she has a rule that if she gets with someone it has to be a devotion to each other forever, and i'm quite willing to do that.

However, while her looks are at least an 8/10, a small part of me feels like I'm settling. I haven't chosen her for her looks, at ALL, I really love her personality, but one of my skills is meeting women and getting them to sleep with me. Really, really attractive women. I feel like I could be missing out if I go with her, but I really want to.

Does anyone have advice?

If you aren't devoted enough that you still feel like you're going to miss out then obviously not.

Well, maybe you should remind yourself how long you have had your aforementioned ability to get women for?
Sleeping around with many different women for short periods could get empty/unfulfilling eventually.
If you do opt for that lifestyle, after a time, you may feel you missed out on the deeper connection you could have had with this one woman.

Btw, I'm not biased to either lifestyle/choice.

ummm looks aren't everything if she treats you right and you have fun and enjoy the time you spend being together it's more important than looks, cuz looks fade.

This is my basic advice I'd give to you as well.

If you really do like this girl, you can't just go for it. You have to consider your nature and make sure you're not going to cheat on her, etc. Good women are hard to find though, although the thrill of chase is addictive you only come across a few good ones, in the bigger picture you won't be missing out on much, just by not having sexual relationships with 10's.

The lifestyle you have is fun for a while, I'm sure, but you're getting older and if you've found a girl you should also try getting used to settling down. What better time to start?