I have used Talley LW on 3 rifles of my own and 2 for a friend and never had a problem with cracking.
From the posts I have read the cracking that you mentioned are from over torquing and not a defective product.
All manufacturers have a recommendation on torque values and if someone decides to tighten it to foot pounds instead of inch pounds you can't blame the product.
I have used these Sportsmatch T084 on 4 different Tikkas over the years and they are tough as nails. They mount to the dovetail on the Tikka receiver and have a recoil lug. There is a taller model if needed (HT073).
I like one piece mounts with a bubble level. I've had good luck with Audere Adversus Gen 2 Scope Mounts and the M-Brace Mount. Both have pita bubble levels.
Also hard to beat IMO, is the 6 screw NF rings with the bubble ring cap.