Chris or other TW staffs! I am about to return my demo kit (V1 10 yr, C10 pro, PS6.0 85, Slaz X1). Thanks for your great service. I've got some questions to ask. 1. Many names are based on their technology (Liquid metal, catapult etc). But what about "Quantum" or "ProStaff"? 2. I really like V1. But the problem is there are total 4 models and 3 of them are being sold at TW for similar price. I've read the feedbacks and will demo quantum and cat version someday but am curious how they compare and which one is considered than the others for what reason etc (if you can answer this question). It's confusing because some say quantum is more precise while the other says it's least liked among three and so on. 3. During the demo session with four racquets, I felt a litte bit of wrist pain. I found V1 is very comfortable. Is 85 less comfortable than the others? Thanks! Tenny.