KB's extensive testing has shown clearly that you can and will make equal or more power with a little less engine compression ratio when using a heat efficient piston.
So the need or real payoff to push the cr limit to the absolute max is just not there, when using their pistons.
My KB pistoned 406 is 9.8:1cr. It punches way above it's weight. Stick to a reliable plan and your 355 will too.