I have a 2010 Electra Glide Ultra Classic( Km 850 ) and removed the cats by cutting header, drill out cat and reweld, it makes a big difference in performance and loader with standard AC and Mufflers. I then fitted the SC AC with V&H Monster Ovals without tuner and with the result of some bottom end power lost, no back firing or popping. The bike was then remapped by means of SC Super Tuner by the HD agent, it now goes like the clappers, next move will be to put it on a Dino to check and fine tune
A previous statement that removing the cat can burn the CO2 sencors I do not think will happen as the cat is posision behind (after) them in the system
I think it was worth removing if the law allows
Jan
Dubai