I've never ran the RB big bore pipe. But I am currently running the Sirio big bore pipe on my Sirio .18tx. The Sirio pipe looks identical to the RB pipe. The big bore pipes like this are kinda old school. I also have ran the Fantom big bore pipe on a fantom .18 the pipes made a big difference in power on the .18 engine never tried them on anything else.
I have that pipe on my maxx but I am running the matching 523
Sounds mean at full noise, better than my picco but I'm unsure how it will go on a 3.3 due to the header gasket as stated before