question, has anyone ever used these?

you usually get what you pay for.... most door popper kits are universal.... id go with kits off sites other then ebay... ebay's kits might last for a few pops but they aren't built to last for to long (mostly plastic internals) but you can find good ones on there too.... just make sure its metal internals on the actuators

protocol is a cheap autoloc knockoff. id go with the spal 7channel kit. its on ebay and its fairly affordable and it comes with poppers.