We pull a 8.5 X 24' King flat nose. Never seen much need for the V nose, because of the odd shape inside is hard to use.
One thing I can tell you, any new enclosed you get, set your mind on getting new tires early, because what will come on them unless you special order a type of tire on the trailer, they will be junk from the factory.
Another thing, would be to have more tie down hooks in the floor, because most enclosed are car hauler trailers & the hooks are in the front & at the rear.
Dont chance traveling & not tyeing every thing down inside either, & use high quality locking straps no less than 5000 lb test each.
One 350~400 lb atv, should have no less that 4 straps on it to lock it in place, keep it from moving & "BE SURE THE GAS PETCOCK IS TURNED OFF".
I've been hauling racing atvs since the mid 80s & you can NEVER have enough tie down strapes holding everything in place.
Neil