I had braces as a teenager and my teeth are still mostly straight, but I have this one lower tooth that was rotating so far forward it was started to push the root into my mouth. It put so much pressure on the permanent retainer bar I'd had since I was 18 or so, that it started to torque an opposite tooth into my mouth and it actually ended up snapping the little bonded retainer bar. I figured it was better to fix it now than have some sort of really horrible problem with that tooth later.
I think the treatment will last about a year. I have to switch the trays to new trays every two weeks.
The first day or two (or five) were pretty hard. My teeth hurt a lot. I ended up having to take Advil so I didn't rip the trays out of my mouth. They also felt unnatural and it took a bit to get used to them. Good thing I've been wearing a nightguard for years or it would have been a totally foreign experience for me. I also found out that when my teeth hurt a lot I get rather irritated and irrationally angry (now how babies react when they are teething makes sense). Now a week and a half later, it's better. My teeth only ache a little while I'm eating, except for on the back right, which still really hurts on and off. I guess I clench my teeth a lot more than I thought I did. We'll see what happens when I switch trays next week.
In terms of comfort, it's weird. Now if I don't have them in, I feel strange (although sometimes I have to convince myself to get up, brush my teeth, and put them back in). The trays are a bit rough and so I have to file them down in places. My tongue is bearing the worst of it. This is unlike braces where my inner lips and cheeks were permanently irritated from the brackets.
I like that I can eat anything I want, I just have to take out the trays first, then brush my teeth and the trays and put them back in. This has actually let to less snacking on my part as I don't often want to deal with the full hassle of it. I don't like that I can't bite my nails. I'm not a big nail biter (anymore), but I like to do it a bit when my nails get too long. Well, maybe this will cure me of that habit.
It hasn't effected my speech, that I can tell. And unless I tell people I have Invisalign, everyone has said they can't even tell.
So, so far so good. I'm very convinced that I made the right decision.