The design of the stock protege rear calipers is a joke...there is a small set screw that is used to retract the caliper piston for pad changes...while a caliper is frequently heat cycled through ranges of nearly 900 degrees F, that is bad enough...but even worse the cap bolt used to 'seal' that set screw does a piss poor job...and more often than not, the caliper is useless after a ridiculously short life cycle...
The MSP rear calipers do not have this...you retract the piston the way most single piston slide calipers work (a disc tool that rotates the piston into its cylinder with a wrench)...so just because of that alone, its a great upgrade...and a DIRECT fit for any 5 lug 3rd gen...no ebrake modification or anything else needs to be done (other than proper rotors and pads, of course)...
sticking rear calipers with ebrake usage is very common though...especially when the ebrake is applied when the rotors are hot, and the ambient temp is very low...its caused by oxidation forming between the iron rotors and metallic elements of the pad material...they're in a way cold welding together, but usually not enough to quickly break free when driving...when its colder, the brake fluid viscosity 'thickens' and tolerances between the caliper slides and everything make it harder to release, thats all...if a caliper is already having problems with a sticking piston, it'll quickly torch everything together...and you'll need a new caliper....
So the MSP calipers can still do this occasionally, too...but a very good layer of high temp grease on the slide pins and pad seats annually will go a long way in preventing this. Also, if its really cold out, try not to yank the ebrake as hard as possible...if your pads are in proper shape, it takes very little cable pressure to lock the car in place even on hills (but always leave it in gear just in case)...