I've been using a two core plastic/aluminum job from NAPA--pretty sure it is a Spectra--and haven't had any issues for almost two years. I've driven a lot on some pretty bumpy roads and I'm sure the radiator has felt it. I don't pull many long, steep grades but there is a 1 mile 10% I drive daily and when grossing just over 11,000 with a couple yards of soil I never see temps over 215-220, but I also have to ease off the throttle due to EGTs. Although my current setup is working just fine, if I needed a new radiator I would probably try a Champion 3 or 4 row just to see if it makes much of a difference. I'm no fan of plastic but eventually I got comfortable leaning my 250lbs on the plastic tank and nothing's broken yet!