Shot 300 with it yesterday at a tourney; first game out of the block. Didn't have a good look thru practice using my Victory Road Solid (similar drill to 503t, but less angular and a little earlier) and VG Nano Pearl.
Threw two shots to close out practice with the 503t-- liked the reaction. I've used it at this house a few times so I knew that if I could get my hand and speed right, it could be a great game.
The second ball was outside my target down lane, but I got a mixer to carry. The 8th was a trip 4-9 (right handed) as I pulled up at the line and gave it more forward roll than normal.
After that, they were all there. The last one was inside target, but it held (come on house pattern!) and carried. Felt good to shoot 3 again, it had been 2 years since my last.
Loving the new Track stuff; own a 716c and the 508a as well. The 716c and 503t make a good 1-2 punch, with the 508a serving mostly as a spare and dry lane ball.