For winging: Duotone 5'5 Aluula Unit, Takuma Ride3 5m, Cabrinha Mantis 4m, Slinshot 3'2, and also Custom Rikyshapes winging with Sabfoil as the biard/foil.
Good question! It's like debating about the gender of angels, like we say in Spain.
Right now, I'm riding strapped on my tabou pocket air after learning strapless on a starboard 4in1 hypernut.
Strapless could lead you to more uncontroled crashes without the control straps bring to you, although, that crashes are painless compared to being caught in a strap on an uncontrolled crash...