From my experience with both. My TS&A is 25% earlier and a bit more continuous on the backend than the UI. For an early rolling ball, I am really impressed with the backend movement of my TS&A. The cover on my UI would pick up oil alot that would create a sheen on the cover and cause the reaction to change a lot. The TS&A is more of a ball for oilier lanes in comparison to the UI, again this is from my personal experience.