Some problems I've seen is that the home work questions are different (how do you do homework then?), and the print quality of some are very low (especially those from India), and many times pages fallout. Also resell value of its used book are a lot worse.
If it is an old book, I'd rather get the US or non-3rd world edition used one rather than a new India edition. Those books from Hong Kong or other more developed nations are generally OK.