Of course the F350 is tougher. Read the brochure ... it's built for at least double the capacity. And for that you will pay double too.

The Raptor is more of a desert runner although it’s off road capabilities are decent I would say it does have a slight advantage over the tremor being a smaller rig. However, the tremor is a pretty stout truck as mentioned above. But it’s huge, when you’re off-roading or crawling around that’s way to much truck for that. So it comes down to what kind of off roading are you doing? Rock crawling,  tight spaces, sand and desert? Get the raptor. Taking you rig off road to hunt or camp, maybe some overland, Tremor.  

It all comes down to what kind of off-roading you need to do.  Around my area where I off-road most of the trails are narrow so neither truck would be appropriate (too wide, too big).  Otherwise on wider trails, especially ones where you can go fast (I.e. Baja) the Raptor would definitely shine over the F-350 Superduty with Tremor Package.  The Raptor was purpose built for such terrain, and can hold its own out there, and the Ford Team had nearly a decade of experience and learnings to fine tune that vehicle for the dirt.  That being said I am not a fan of the newer F-150 Raptor with the 3.5L V6 Ecoboost engine and 10-speed AT.  I’d rather go back a generation to the 2014 Raptor with the 6.2L V8 mated to the 6-speed AT (that’s a better combo for longevity, if you plan to keep your trucks for a long time).  Also, as a work truck the Raptor is not ideal.  For that reason I would go with the Ford Superduty (although I’d stop at the F250 level) and with non-diesel to keep (expensive repair) costs down in the future (if I keep it long enough).  At the same time, the prices are astronomical on all these trucks, but I can’t recommend the Raptor.  I’d go F250 with Tremor and split the difference:

https://m.youtube.com/watch?v=ugldzNjuWrw