personally i think there are far safer alternatives, 25i isn't that special to risk your life over it. I say this after accidentally taking a shit load of it and using it recreationally before that. Never wanted to even risk that kind of thing again. These drugs are too potent and do not have a long enough history of use to say anything for sure.
if you're going to take it anyway, start low, for whatever reason i found 2-3mg to be a decent trip, but people respond unpredictably to this drug, with many reporting strong effects from low doses and a number of deaths from what would be a reasonable dose for me.