i own and work 2 GM medium duty trucks. an old C65 dump that still makes money. also, a 4500 4wd dump truck with the duramax/allison combo. i drove the ford 450 and 550 prior to buying the gm and am very happy with my decision. both trucks work very hard and have been overloaded a time or two. the 4wd system on the 4500 has been flawless. the turning radius on the gm is also tighter than the ford or dodge offering. i also like the 4500 body style, the visibilty is great from it. the turning radius and visibilty make a big diffrence in the areas i often work. the 5:13 gear ratio also is great when towing heavy up mountains. the arguement against the newer medium duty trucks doesn't hold water in my mind. i think GM lost the medium duty market prior to the new trucks. they went a long time living off the older style trucks and didn't try to compete in the 4500-5500 market till it was too late. the late 90's ford super duty and 450 550 were great trucks and during that time it seems ford started really taking over the medium duty market. the sad thing we are all poorer having lost GM's medium duty division. attached is a picture taken on top of Rich Mountain outside Boone N.C.. i was towing a backhoe in 4-6 inches of snow up and around the mountain. there was 3 tons of topsoil in the bed as well. i think they hold their own well.