aside from them looking super trick, what is the advantage to one of these pipes compared to say a fmf or similar?
Huge difference,had a HGS and a pc both complete with silencers. The pc was great for rushing the motor threw the powerband,great for corners then having a huge jump to clear. The HGS had way more mid,much wider mid pull,had lowend torque that I couldn,t believe,topend rev and pull was stronger than the pc pipe which is a great pipe. That was on a 01 RM125. I have a BUDD Racing HGS from a 03 KX125 on my 04 cr125, alot of bending the tail section along with sawing, then pounding the pipe in for clearance for the kick starter and radiator hose. HGS has a junk of lowend, takes a mila second then strong lower mid hit,then pulls harder and further than the pc setup,then adds 3k more of over rev more than the pc setup. The pc setup is still great,comes on the pipe quicker,then rips threw the powerband. PC makes a better pipe for honda 125,than FMF. Fyi Scalvini makes the pipe on the Husky 125,it,s on Scalvini ,s site.