Have a china 372xp. Works pretty well actually. Will it be as tough as the original? Probably not, but they sure are fun to try and modify and work on.
I can buy a china 372xp muffler for like €4 and try a bigger outlet or a dual outlet or an outlet on top with deflector...... If you want to have a go at porting, but don't wanna trash a good quality cylinder, you can for a fraction of the cost.
Put a aftermarket dual port ms440 muffler on a ps7900. Worked great and looks pretty good to. Didn't cost a thing
They definitely have their place, someone here posted 300.00 for a 9010 makita
muffler now with the shortages, that's just not right, a muffler should be a simple
task to manufacture though, no super critical accuracy required like that involved in making sure cases, crank, rod and the likes all line up with the cylinder perfectly.
Seen a guy on another site, new china 660 clone, less than a half tank most
of it idling to oil the saw up before he started, scored the piston doing nothing
more, that's how long the saw went before major failure, said metal and fuel
came out the muffler.
@Wilhelm , muffler for your Dolmars mentioned above,
wish I knew about the MS440 muffler fitting a 7900, I spent
a while prising open the one on mine, drilling out the cage
and enlarging the outlet more and cleaning all up and re assembling.
When the China saws were real cheap, they were worth a go, not so much now,
you could get a good one, or a bad one, not worth the risk.