I believe your answer lies in the quality of the build and the builders as well as how performance bent you are. If solid builders construct your motor, tranny, wiring and body, and the suspension is set up properly, then that's half the battle. The other half is in how far you went as far as performance. The farther you travel up the horse power curve and the more complex the motor, the more likely a chance for a problem to arise. Your Suburban makes you feel comfortable about reliability because engineers designed it within parameters that would allow good road manners, good performance and good reliability. Certain things were probably compromised, like additional performance, in order to do this. My Cobra was built with performance first, reliability second and gas mileage third. I take the old Harley approach to long trips in it. If it breaks, have the tools and parts to fix it. If I wanted a long distance Cobra I would have gone with a modern day small block with fuel injection, not a 60's giant chuck of metal (428FE) with a barely streetable cam. That's my $.02
--Mike