been in the bus. for 25 yrs. as a tech. mercs and corsas are nice kits and work well!on my last boat , i installed imco's kit. Imco makes quality stuff too! it was priced rite, that was 6 yrs. ago, but the thing i liked about it was that i could set it anwhere in between, not just full on or off! they also sell all the tips, elbows ect..