Right there with you Balsa Bandit...
The first time you see the smoke billowing on the ground... I mean displacing a nearby parked Honda Civic or F-150... it gives me chills and giggles. When you completely loose sight of the entire tail section during a low-level inverted, nose-high pass is when my pants get a bit tight. My Yellow Sukhoi is going up next week (armed with another TME/Saito 180 config like our other Yellows) and I'm chomping at the bit!
Outcast is right with the slight messy oil n'gas burn of the TME system, but coupled with the usual four-stroke muffler debris, a quickie windex clean-up is an easy fix.
-Juhan