OMG - do it. I am 51 and got them two years ago. I had metal braces at 9 and the again at 13. Back then, they didn't tell you to wear the retainer for perpetuity (I would have done it if I knew).
Over time, the teeth shifted and I toyed with the idea but didn't jump in until I found a great ortho through a personal recommendation.
I am SO glad I did! My teeth are straight again. You can bet I will wear my retainer for ever, though eventually it's supposed to get to once or twice a week. My best friend saw how happy I was & saw my teeth and now she & her 18 yr old son are doing it together (and his teeth are really crooked, so it's not just for minor corrections, but every case is different). Her co-worker is now doing it as a result of seeing her progress, and another neighbor is doing it after seeing mine. Crazy!
It's not uncommon for teeth to keep move as an adult teeth (lots of stuff shifts w/ age!) so be prepared to wear that retainer.
There's been so many advances in orthodontics over the years. There are even different kinds of metal braces if that's what you opt for.
The BEST new thing is now they have digital impressions!! High accuracy and no gelatinous glop gagging you for 3 minutes!! Yay!!! (I still had some parts of treatment that required some of the old school impressions, but even those are better nowadays).
I loved the Invisalign as I could remove them when I had to do presentations for work, etc.
The pics & ads don't really convey all that is involved, though. I thought my top teeth were fine (they looked it compared to the bottom) but in truth, the whole bite needed to be aligned. You will probably end up with these "buttons" or "notches" - tooth colored attachments to the teeth to 'anchor' the braces and aid in specific movement. You will be self-conscious but hardly anyone will know you have them. I even had two of them on one of my front teeth. I even had to wear a rubber band at one phase in my treatment (oh well).
But it goes quickly and the results are worth it, and IMO it's still a better alternative to the traditional braces of yesteryear.
Every day I am SO glad I did this. My dr. was what's called an "elite' Invisalign provider - something to do with how many cases he does (he does a lot). Maybe look for one of those.
I'd say his practice is about 40% adults to 50% kids.
Like anything else, it's about choosing the right person to do it! Word of mouth (pun intended) is the best. Start asking around - I bet you'll find a lot of people have had or know someone who's had them.
Good luck!! PM me if you are in the So CA area and I'll give you my guy's name.