5-IAI (even the real stuff) fell miles short of expectations. It's not particularly notable - it's a decent stimulant, with a distinct feeling that it's more than just a stim, but it doesn't have any magic (this + 6-APB should by now have drilled it into our heads, that triple release is not sufficient for MDMA-mimetic effects).
This is part of the reason vendors aren't stocking it. The production problems were never solved because the pilot runs were tasted, and were deemed to not be any good, and so it wasn't worth it to front the money to optimize the process, because it was clear that the product wouldn't sell after real world reports started filtering in. 5-IAI isn't the "fiendable molly" that everyone hoped it would be - it's just a short acting, strange-feeling stimulant, that's far harder and more expensive to make than a wide variety of much better drugs.
Leave out the 5-IAI, and prepare for quite a ride with 10mg of 2C-P, that stuff is serious buisness in and of itself.
Never do a combo the first time you take a drug.
And, i have to wonder, why 2C-P for your first phen? It's a bit of an odd phen - 2C-E/I/T-2 are all more natural choices than 2C-P... Or for that matter, any other 2C except 2C-T-4.