Are these identical to the US versions? Form the research I have done, they appear to be, but this is a math text, so I want to be sure the problem sets are the same.

I'm pretty sure they are. The reason they don't want you to have them in the US is the huge difference in price. They are really upping the price on american texts to subsidize the rest of the world. I can't be 100% confident that they are exactly 100% copy but I'm pretty sure they are. Probably google to check.

there's a site called textbooksrus.com that only sells the identical content international versions. I had a physics book where they switched problems around for the international and it didn't show up there. I figure if they sell it is good enough for sure

That is a great thing to look at. I will see if they are selling this book. I should have known there was a reason it was super cheap in the Amazon market place.

edit to add: I took a look and they offer the book for sale. I see they guarantee the text is identical, so I figure I am ok.

They are almost always identical in content, but it'll be paperback with very thin pages and all in black and white. Definitely worth the cost savings.

I bought one, not even knowing it was international edition, and it was identical. However when I went to sell it back they said they cant buy international versions so I kinda got screwed