I have both. The 4UP is waterproof, slightly smaller and lighter than my Players4. Stands slightly more upright so you have to watch it a bit on windy days. Straps are a bit less padded but that was an easy fix for me as i added seatbelt pads i got from the local auto-parts store. 4UP pocket positions are more traditional than the Players4 as you can see by comparing pictures on the website. I really like them both a lot. You cant go wrong with either. Mainly, get your Titleist sticks in a bag worthy of their pedigree. :)

Cool thanks for the feedback

Ended up going for the 4up, the ultralight weight design sold it for me, delighted