Thank you for the support bradl!
I drilled an Obsession Tour with the same layout as the GB4. The Obsession definitely has a stronger coverstock than the GB4 and if it would have been a solo video I would have included a surface change up to 3k by the spinner to see how it would actually be usable in your bag at a more normal grit. Clean backends and my decision to be a little more aggressive with my hand than usual to contrast Barks made the GB4 look a stronger than advertised and I wouldn't recommend many league bowlers on a THS to be keeping any ball at 1500 grit.
The Obsession Tour is the earliest of the 3 balls you listed, with the Widow being the most responsive to friction (just a tad stronger than my Omni). The GB4 will be the weakest - especially once the coverstock is no longer covered in charcoal. Barks' GB4 was a lot weaker than mine in the video as he had put 6 games on it earlier in the week (laneshining the ball), while my ball was drilled that night and I only took 2 practice shots with it prior to recording the video.
Clean backends and my decision to be a little more aggressive with my hand than usual to contrast Barks made the GB4 look a stronger than advertised and I wouldn't recommend many league bowlers on a THS to be keeping any ball at 1500 grit.
I'll add that I instantly took my GB4 to 3000 because the out of box 1500 is definitely too much. It's been great for me so far. I also drilled an Obsession Solid, both are great compliments to each other. GB4 as strong benchmark and Obsession as the ball up with more cover and more motion.
Interesting thoughts. Thank you both for that. This then tells me that I could use the GB4, take it to 3000, and that would make a good benchmark piece. Then either go BW 2.0, Web Tour Hybrid Edition, then a pearl underneath all of that, and should make a well rounded bag.
This helps, because I was trying to find a way to talk myself OUT of getting a GB4! Now I actually might need it, as I have one more hole in the bag to fill.
BL.