Doing some other comparison testing...
Update:
O.K. so i finished that... i used a different (official) client to compare this with the Fgunz client.
Same settings on both, with fgunz special settings all disabled or turned off.
fgunz client: 250 fps smoke appears rarely, 1000 fps smoke appears rarely
other client: 250 fps smoke appears rarely, 1000 fps smoke appears always
Thats all i can really say.