Rhino shafts fit perfectly. I did add a 13gr weight over the pin to get the balance I wanted, also have an 8 gr weight that I use on another cue. I don't use the weight with their Ultra shafts. I play with the Ultra shafts, but I bought a Rhino shaft for a backup. I's a really nice shaft. When my wife stole my Jacoby from me, she wanted the Rhino shaft on like she uses on her Schon, but wanted it to feel the same, so I slipped a weight over the pin. Simple, simple, sadly she loves it now so I don't think I am getting it back, or I should say I won't get it back till I buy another cue, and then she will like that one, ha ha.
As to why she likes the carbon shaft, because she doesn't have to wear a glove, a.nd it's nice and slippery. The Rhino plays very similar to the Ultra shaft.
Edit, Jacoby also make a great carbon quick release extension, pricy, but fantastic.