I have a fair bit of experience from snorting, and pretty much the significant difference it makes is that it is a lot speedier at the beginning, and that it takes a while for the empathogenic effects to come on (as compared to the speedy effects. The empathy effects come on quicker than when taken orally, obviously). Genereally when I snort MDMA, I'll be high as a kite in 15 minutes after railing it (I rail powder, I wouldn't want to rail pills due to binders, which may block up your nose and make it more irritated than powder) and will generally plateau for 2-3 hours then comedown. An oral MDMA dose would keep me high for about 6 hours, while I'd say a nasal dose keeps me going for 4 hours.
I don't really mind the shorter duration of railing MDMA - I'm not one to stay out partying until 4am, so I much prefer my drugs to be shorter acting than longer acting. I want to be able to sleep before 1am goddammit!