We run both.I have been into nitro for 13 years and I have never seen a engine turn the rpm's my Rossi turns.It makes me want a 5 port now.The top end is simply awesome...Let me add I bought it used for $125.Was that a good deal?But I'm getting another NTC3 and put my brand new Sirio AAC 5 port in it.I want to see how strong it is compared to the Rossi.