Welcome to the IPS forums, have a free (+) from me.
I've been using IPB for a number of years now and am quite pleased with the product. Yes, there are times when they don't include an option that I think they should or make changes that I wish they wouldn't, but that's a part of life with any product. I'm one of those who was hoping IPB would go on one more testing release before going final, but oh well. IPS definitely stands behind its product and does its best to fix the bugs that are found, no matter how insignificant some bugs may be.
When you take the plunge, I encourage you to give consideration to the community suite, as they will give you an up front discount of $15 (you get IP.Board, IP.Blog and IP.Gallery) and then the optional renewal fee is $25/6 months. After the first year, you will end up saving $50/year that way. Of course, renewal is optional but when you do decide to renew (even if it's a year after the invoice has expired), you just pay $25 and everything is considered up to date again.
So welcome to the IPS world and I hope you enjoy your stay here. :)