I do. All I can say is that is requires lots of practice, especially if you haven't grown-up with the music and are a complete newbie to dance. At first it's really tough cause you have to get used to the music, learn to lead, etc. You'll eventually get to a point where new steps come a lot more easily b/c you've got the basics down well enough.
I would highly advise taking lessons. Both group and private can be of value and offer different things in return. With private lessons, you'll develop better technique early-on, however you'll lack the crucial experience of dancing with lots of different partners, which is a benefit of group lessons. Overall I find that I get more from private though (and my instructor is a cutie) since I find that i learn faster than a lot of the women in the public classes.
You have to get used to dancing with different people if you're ever going to go to the clubs. Salsa is very social, and most people switch partners after every dance. Obviously, you don't have to, especially if you're with your gf, but still, it's good to learn to dance with more than one person. If you're always dancing with the same person they learn to read you very well, and so your leading might be really weak but you'd never know.
If you're gonna take lessons, you should hit the clubs at least once a week to practice or you'll be wasting your money imo. Either that or practice with your gf a couple times a week. They say most guys have an exponential curve in salsa. They get better very slowly at first, but eventually take-off when everything clicks. Can your gf dance btw? If so you've got a huge advantage over most guys trying to learn. I find it significantly easier to dance with good partners than people that are also learning since they're much better at following.
I'm actually talking to the girl i'm seeing now about taking salsa lessons with me. She's also got mexican blood. She wants to do ballroom though, so we'll see. I'd rather get good at salsa first before giving too much attention to anything else, especially givne my extremely limited free-time lately...
Anyway, it's a ton of fun and a great way to meet lots of women. If I'm in a bad mood from work i just go to salsa and I forget all about what pissed me off.