Maybe I'll get lucky and my stealth fretless will ship with these?
It'll probably ship with the standard Slinkies but you can order them from your supplier and have them install for you or ship with the bass. Or you can buy a set to have ready when it's delivered.
I like flats for my fretless partly because I don't like the fingerboard wear from rounds so having some super lively flats would be pretty cool imo