How to mouse click on both sides of a double sided texture?

Almost?
Line trace is non physical.
You should run the test with touch simulation - such as having each plane slam into the other domino like.

That will tell you if physics are affected in any dofferent eay between 2 tris as complex and 1 cube as simple.

If we are taking bets, I’m betting the cube primitive will run a ton faster.

Additionally, anyone can safely bet that a domino like plane scenario will become unusable with chaos after around XxX instances.

My guess is around 400 bodies (unusable = sub 30fps at 4k native limited by CPU).

Ehile physx would survive to around 1500 or so.