Usually B-12 comes in mcg/ml. Not sure what ug is all about. As far as mixing them all together in the same syringe goes, it should not be a problem, providing all that gear can fit in one syringe. When I shoot mine, I usually will onle take 1cc a week.
ug or ucg and mcg are the same thing, units of micrograms. The "u" is actually supposed to be a greek mu symbol, but since no one wants to type in that special symbol they just use the letter u instead.
ive been running 3 cc a week - same strenght.
i dont see how you can get to much, i guess you would just piss it out, but its dirt cheep where i live, $5 for a ten cc bottle