you guys can't compare a modified 7.3 to STOCK vehicles.
for example, my 04 cummins with a smarty will outrun any 7.3 with a tuner. why? because a 7.3 can't make 430 rwhp with just a tuner. and a 6.0 with a good tuner will beat any 7.3 hands down. stock 7.3 powder rods can't reliably handle over 400 rear wheel horsepower anyways.
i prefer cummins. easy to modify, has more longevity than the other motors. however, if you're not into hot rodding, find whatever you like and run it. they all
have their own set of problems