Although I am tempted to find the orig rear derailer, I really like the way this one works, very smooth, very easy shifting, as for fire fighting, I havnt done it for about six years now, due to injury, but I dont miss running around soaked in water in freeezing temps! LOL! we used to go back into the fire to keep warm! LOL! I think about it now and it still sounds crazy! LOL! my Ferrari bike is actually a Derby, it was a rusted out POS when I got it, so I just painted the frame and slapped ever part it needed on it including autnebtic Ferrari decals! and whalla! Ferrari Bikeinstein came to life! but heres are two pic, before and after, of my all orig Colsen Commander (thanks guy for not making me remove the pics) note the NOS Delta Rocket light! I have the NOS rear light just havnt mounted it yet.