You could get away with owning just Mandelin if you only want to know whether your pill contains MDMA, MDA or MDEA. Or if it contains Ketamine or Speed/Meth alone. And you also do not need to keep Mandelin in the fridge. Marquis needs a fridge to stay alive a long time. Kits can stay alive for well over a year if kept in proper conditions, probably longer, but the reaction times get poorer at about the 2 year mark. Both kitys don't cost much, about as much s you would pay for as pill at a rave, and could either save you a lot of money before buying in bulk, or potentially stop you from taking a harmful pill.