Lephturn, if you are looking for road bike, you should consider a true, heavy-load touring bike such as a Trek 520.
The wheels and tires are wide and stout enough to do the job--they carry riders and full cargo loads long distances--and will hold up under a "beefy" load! The frames are also designed for weight carrying.
Although I am a "featherweight" compared to you guys (5'5" female, approx.220-225 lbs.), I also carry a lot of heavy loads with the Trek 520 I have...plus the "load" of
me!!!
The wheels and hubs have held up with no problem (I often use a cargo trailer with a hub mount hitch as well!!).
