A lot depends on the year you are looking at and what your personal preference's are. I have an old 454 that develops max torque at 1800 rpms. When I first tested the V-10 I thought the engine was very noisy because it developed its max torque at a much higher rpm. The newer V-10's that I tested seemed much quieter. By 2006 the performance of both engines were similar. For me I would choose the Workhorse chassis over the Ford because of the 6 speed Allison transmission everything else being equal. The new Fords are coming out with a 6 speed also.