after 3 years 10 or 15 will feel pretty much the same anyway, but if you are snorting like I was, the 15 is a little stronger since it has 5 more mg of
oxycodone, which is the narcotic in both of the pills you mentioned...good luck with the sub, I have been on for 4mos...it helps alot with the physical w/d, but you really have to want to stop in your mind to be successful with it.
how much oxy are you on a day? if its not too much you should really try to use the sub as a step down to getting clean...dont get stuck in the indefinite maintenance program like so many of us...