snorting it will kick in faster, but reduce how long they last.
snorting it will also increase your tolerance quickly, like the first comment said "So it begins"
you will soon need more and more to receive the same feeling, because the instant feeling you get from snorting will become less prevalent as time goes on.
the same thing will happen taking orally, but it will take longer. i suggest you take it orally as prescribed, snorting is increasing the chance you'll become an addict to the feeling you get from the instant euphoria and pain relief from nasal consumption.
take it from me dude, started off snorting pain meds now im a heroin addict. you think it'll never happen but you never know.
i suggest you drink cranberry juice 15 minutes before you take your pill, that will increase how much absorbed and make the opana stronger so you get more out of it. also take a benadryl 15 minutes before, that will also increase how much hits you.
if you do plan on snorting, id only use a half of a pill to start, that should be enough. when you snort it, even a half will feel stronger than a whole one taken by mouth.
make sure you know the procedure to blowing your meds, or you could end up wasting it. Shoot me a pm if you have any questions, prescription meds, especially opiates are my main thing. i could give you better advice than a doctor in that aspect

haha
good luck with whatever you choose brother, just be careful.