This is one of the better ideas I've heard alright. I don't mind leaving the comp running for an extended period for the test if you like - I'm at work 9-12hrs a day, so would be no prob to have it up and running for that time.
System specs are 1.7 P4, 512 ram, geforce4 4200TI, win XP pro, DX9b, so should be about average system in use. There's not a hell of a lot running on my system in the background, so shouldn't be a great deal of interference issues to worry about.
Provide the build and mission, I'll run the test and supply the error reports. Beyond that though, what little personal time I get is spread very thin.
H