hey guys and gals. i was wondering what some of the differences are between all the exhaust pipes to choose from.

like are ones with dual exhaust outlets better than single outlets.
and will there be a difference in the note of the engine with different pipe?

i'm not into racing yet so i don't need to go all out. but it's still fun to buy hop ups.

should i just buy the one that i think looks the coolest?

i just bought the mbx pro with the .25...how's the exhaust that came with it? will it be good enough?

lastly will pipes for .21 engines fit my .25?

any help will be appreciated. thanks