i have had great luck with Goodyear marathon radials. i wore out a set with no blowouts and bought another set and they are half gone. no problems ever!
just a side note i have a 20 foot car hauler and its been all over the united states. went to iowa about 10 times and florida and back a couple times. not to mention all the michigan miles i put on them evey year. i put alot of miles on these tires and they wore great loaded and un-loaded.
i dont recall where i got them, (i work at a shop and told the service writer what i wanted and he got them for me)