If you beat prime with Titanium/Hallowed, I'd go for Turtle, only because it's a precursor to Beetle Armor. I wouldn't really wear the Turtle armor itself, and I'd stick with Titanium. Hallowed Armor is a fine alternative to Chlorophyte so you'd do decently with it.
If Adamantite, then I'd upgrade to Chlorophyte if you want better benefits. You can always craft turtle armor with any spare chloro bars you have. Turtle shells will come by as you look around the jungle for those ore.
Or you can always just get all of em. Unless rng decides to screw you apart, it should be all fine and dandy.