i have had a gms 61 and now have a gms 76.
for the money you cant beat the horsepower you get out of these engines.
its all in the break in. this engine is not very reliable untill its broken in.
and i mean about a gallon of fuel.

also the low end needle on mine was way off.and very senitive.
they also run better with the stock muff too.
once you get past the breakin you ll have a cheap power house that ll swing a 15 in prop no prob.