Both engines are fine machines, but there's so much more than just the engine.
I've had both, but my comparison is not a fair one:
2000 ('99 chassis) 27' Four Winds 5000 on E-350 with the anemic V10/4spd
2016 ('15 chassis) 24' Sunseeker 2250 on 4500 with the modern 6 spd.
Yet, I wouldn't own another Ford for many reasons other than engine/transmission.
Having lived through many horrible experiences with bait-n-switch Ford dealers, expensive front suspension mods, cramped legroom, hot doghouse, fuel pump failure, etc, I was overjoyed to join the Chevy club.
The 4500 is not without its faults, but all in all, it's a much better chassis than Ford.