Even though I read the reviews and was aware of the cracking potential, i thought I was smarter. I used a threaded drillbit after pre-drilling and all was well. The second I went to install my mid-range....crack. i wound up buying some ABS from amazon and using these as a template then threw them away. I believe these are acrylic. Id scrap that idea and juat use HDPE or ABS, neither of those should crack.
Build quality and fitment was perfect, unfortunately the application failed.