Drilled my Bruiser 4.25"x40 with the intention of having a middle of the arsenal type ball for use on multiple patterns.
I really liked the original Knockout for medium lanes - particularly as they started to dry out and I wanted to move my feet left yet see a big hard arc on the back end. The Black/Blue was a lot earlier rolling and more controllable down lane, which suits my eye on tougher and shorter patterns.
My assumption was that the Bruiser would fit somewhere close to the Black/Blue but with a bit more motion down the lane. I was wrong. This ball really reacted strong at the breakpoint - stronger than even the original.
I have used this ball on 3 different patterns - 9/1 42' heavy oiled league pattern, a 45' challenge pattern and the 39' Masters Pattern. My look in league was alright, although my carry was a bit suspect as this ball just wanted to turn so sharply on the back end. Strong wrap 10's and solid 9's were just the result of a ball that was reacting too violently on the back end when the shot for me was to play a little smoother and straighter.
Conversely, this ball has been incredible on our 45' challenge pattern. It plays a bit on the drier side so finding a ball that would get through the fronts clean and take advantage of the limited dry boards at the end of the pattern has been the right play. The Knockout Bruiser has done everything I have needed on this pattern - clear the fronts and respond hard to the friction at the end of the pattern. You will see a few shots in my video ball review of what that shape and tremendous down lane recovery look like.
My shot on tougher patterns hasn't been so good with this ball and I really didn't expect it to be. The Knockout Bruiser is just too sensitive to oil and dry boards to be effective on a fresh sport pattern. I had some extra recovery to the right that was unexpected, but pretty much zero hold area as this ball wanted to cut loose once it hit the dry boards. Maybe after a few games + some carrydown it would have been fine, but I have other options in my bag for these patterns
Compared to other balls in my bag it is my most angular solid and closest to my Obsession Tour Pearl. It is a ball I can switch to when my benchmark balls (Verge Solid/Obsession Tour Solid) are reading a bit early or are looking lazy through the pins, but isn't as shapely as some of my high end pearl pieces (Quantum Evo). It compliments the Black/blue as being a longer/sharper ball to switch to if you need to see more shape on the lane and would be a great replacement if your original Knockout has seen better days.
I really think this ball would roll well for bowlers with lower ball speed/revs or a more forward/heavy roll. The Knockout Bruiser would also be a great option for league in houses with a more beat up lane surface (or wood) where the huge high end cores are just too early, yet you still want to see some strong motion.
https://www.youtube.com/watch?v=k8lWq2PctLM&t=489s