Congratulations and welcome to the forum. I have owned a Cardinal 3800FL and a 35 foot Work and Play 5th wheel. Loved them both. Take this for what it's worth, you will be looking for a bigger truck for the Cardinal soon. I towed my Cardinal with A 2013 F35O dully and it was all it wanted. That is a heavy and long trailer. I am sure the F250 tows it but you would be amazed at the difference moving up to a dully. Again, not trying to be the weight police just stating real world expierence.
Take this for what it's worth, you will be looking for a bigger truck for the Cardinal soon.
Yes. We have discussed this exact thing. As of now, we've only made 1 short trip other than bringing it home. Even though it's within the capacity of the truck, it's at the upper limit and the consensus is a duelly is better.