usually a molly cap is about 80-120mg of mdxx. it could be either mdma or mda. mda would give you a stronger, more.... happy trip i guess you could say. if you get molly, look in the cap, it should be crystalized. you can crush it up and snort it... or just take the cap. don't mix it with other pills though... cause then you are wasting it... get some caffeine pills or drink 2 or 3 redbulls..
dealers have their hands in molly as well, so i'm sure there are alot of 'molly' caps going around that are cut with other bs.