Towing > 40ft - drw vs srw?

I have a triple axle toy hauler with a top weight of 18k pounds. Four years ago I research the heck out of the type of tow vehicle to get and decided on a drw. I ended up with a 2009 F-450, but unfortunately someone decided to pull out in front of me last week and it totaled my truck. Now I’m in the market again and it’s just hard to find a good drw for a good price. I am still leaning towards a drw, but maybe it’s overkill. I notice a lot of people towing similar or larger campers with srw 350 or 3500s. My question is for those people - do you feel safe or wish you had gone with a drw? How about any sway? I do mostly flat towing with very little mountains. I appreciate any comments and it sucks to have to look for a new truck. My F-450 was solid.