I prefer whole, seems to cook better.
Plus, pulled pork is great reheated. Freeze it in Ziplock freezer bags or vacuum seal it. Come dinner time one evening, pull it out, toss it in boiling water and 30 mins later you've got dinner that tastes fresh!
Homemade trailer Roaster a.k.a "Hog-A-Nator"; UDS; Dual Chamber Charcoal; ECO Gasser