I'm with Dogman! The bullet hitting the RPG while both are in the air traveling towards each other was the best test yet!
As for cats, I agree, there is a time and a place, when I had my 85 Subaru Brat, (note the year, the WORST year for emissions) I removed 90% of it, added a higher performance weber carb, and gained almost 4 MPG!
Sure all that stuff can work well when it's brand new and perfectly maintained, once it starts to wear out, it makes things worse.
I also added my own home brew "condensator" (imagine a filter of sorts that goes between your PCV valve to separate all the heavy stuff out before it goes back into the intake) and that cleaned things up a ton, kept more fuel available to re-burn and caught what little oil and water in that line that would have done nothing but make things worse at the intake.
When my exhaust needed replacement, I did not replace the cat, but I did retain the exhaust design to properly scavenge, and again, gained more MPG, low end power (I built it primarily for off-road) and the thing that cracked me up was my mechanic giving me crap about it when he rides a snowmobile which is a 2-stroke, and he's out in the most pristine high altitude snow fields spewing smoke!
Don't get me wrong, I agree it makes sense especially in areas with inversion layers that trap in smog, such as LA, an yeah, Missoula Montana has some of that trouble too, but it's really funny when you have laws that restrict pollution, and then during fire season some of the same people who want these laws also want to let forest fires to burn because it's "nature" and you can't see more than 2 blocks because of the smoke, but it's the CAR emissions that matter?!
How many of the "evil bad gasses" will be found to be less harmful yet again? We have already had laws needed to be changed because the "less evil gasses" that we replaced the "bad ones" with turned out to be far worse than ones thought to be harmful, how many more times is that going to happen before we calm down and use some common sense?
I think these days we have hearts in the right place, but too many are looking at things with a microscope instead of seeing the bigger picture.
For example, how many of you realize that the electricity you are using is mostly produced in the USA with COAL!?
Unless you're lucky enough to live close to a Nuclear power plant or Hydro electric plant, you are fooling yourself thinking an electric vehicle is producing less pollution, the truth is, you're just not seeing it come out an exhaust pipe. More pollution by far is going into the atmosphere while producing electricity with coal than all the SUV's combined.
I too want to see something replace ICE's, but at the moment, nothing is more efficient (does more work pound for pound than any other fuel) or cost effective, even to include pollution.
There is some interesting fuel cell development using Natural Gas that might replace ICE, but it's still to be determined if it's able to take the place of ICE's.
http://www.katu.com/news/business/130871068.html
The fuel cells, which convert natural gas into electricity and heat, were made by Hillsboro-based ClearEdge Power. According to ClearEdge, their fuel cells are 10 times more productive than solar power.They will be used to power Sylvania's Health Technology Building and to heat the swimming pool that's inside.
http://sustainablebusinessoregon.com/ar ... cells.html
a 5-kilowatt fuel cell roughly the size of a refrigerator that combines heat and power using an electrochemical process and natural gas, reducing overall emissions. The ClearEdge5 carries a list price of $56,000.
) Carbon Monoxide (~8000% More than cars)
NOs might be high, but imagine what it would be like with a dry shot 
Suzuki SP200, Mars Brushless, 300 Amp Kelly Controller,(18S12P) 
which is what most people try to make go fast, i.e Crapmaro's, Mudstains, small penis sporting balding Corvette owners (some of the dumbest around), etc.
