just purchased a 505T to put in between my 715T and 607A, it rolls really nice, reminds me of the Mutant Cell but a bit weaker, same motion. I have 715T at 2000Ab, 505T at 4000ab and 607A at 1000 polished. All drilled identical 65x4.5x30
The 715 has been great for me, 18 games, lowest 192 only game under 200..high 276 averaging over 225 with it. I am very happy with 505T also, shot 635 and didnt hit my mark as consistent as i usually do, I think the 3 balls fit togther very well. The 505T is my new benchmark ball