While on subutex, and for several days afterward due to the drugs very long half life, consuming other opiates literally won't do a damn thing recreational speaking. You could eat 80mg of oxy and it wouldn't do shit. Not even dope. Bupe binds to your opiod receptors so strongly.. That it prevents other less strong opiods from even having a chance. You have to stop taking sub's for I'd say a good week or two depending on your use for you to get high off normal pharms again, and even then your tolerance will still be pretty high. Sub's can save your life when you need them and can even be enjoyable the first couple times you take them. But the withdrawals from them are horrid and they have a ceiling effect around 32mg.
I don't screw around with sub's anymore it got to where I needed them to function. Screw that man. Just give me a few oxys every once in a while and I'm good.
I will say though, a light dose of sub is great for the day after an oxy or hydrocodone binge. Takes those shitty feelings away. But no more than that.