Seeing as shooting up oxycontin/oxycodone (IV use) doesn't give a "rush" or even a significantly stronger high compared to oral administration, I'd assume there is no benefit to plugging the stuff. And actually, I'd think there's a good chance the high you get will be WEAKER than the high you woulda gotten via oral or nasal use.
I say that b/c the BA for oral is so high that if anything, I'd think the BA for plugging is lower, or at best, equal to the oral BA. And on top of that, rectal absorption is effected by how clean your rectum is, I imagine everyone has some built up feces in their rectum, and therefore doubt anyone has 100% of the surfaces in their rectum exposed and able to absorb the oxy. Plus, technique plays a big role in how effective plugging is: how deep the solution is inserted, how much or how little fluid is used, how concentrated the solution is, what position one is in during and immediately after administration, and how well the solution is prepared.
So unless you have perfect technique and are well experienced, the actual high you get will be weaker than what was theoretically possible b/c of all these variables....
B/c of all these issues I'd say that even with perfect technique, the BA and the high will be weaker than what is theoretically possible from plugging. Combined with the fact that most people say Oxy doesn't even give a rush/better high when injected vs orally taken, I'd say plugging is weaker, has lower BA and gives a less intense high than eating or snorting would give.
And IME plugging is never worth it, never better than the alternative ROAs (not including IV) and just not worth it. Maybe a chem like Dilaudid or MDMA would feel better plugged than eaten, but as far as Oxy goes, ESPECIALLY
With the original formula--crush up and snort or swallow
And whatever you do pls be careful. Some ppl still insist plugging is right below IV, so if you do plug, don't use more than you would take orally or snorted to compensate for what I've mentioned above--just take ur usual dose and see what happens..