Based on my experiences with the 2. I bought a Red firefish over a year ago, still have have him and he's very calm but i also have percula clownfish and green chromis and they are very hyper. i bought a purple firefish had him for about 3-4 months. they got along great! very beautiful fish. died, not sure why or what. then i bought another red one. the first 2 weeks the old one was stressed moved out of his rock and to the other side of the tank. it even looked like his fins where getting smaller. i thought i was going to lose him. three new one would chase when near. but now they are fine together. they aren't close friends but dont go after each other orhide from each other.
also the purple is like 20 bucks more. and even though they are jumpers. i've never had any jump. i have even had my lid off while cleaning or changing water. never jumped once. but i have plexi glass on the back lid by the filters.
hope that helps. good luck