If it is internally gated, the spring is far enough away from the heat I would think.
I am running all 3 Turbosmart springs, and the heaviest they will sell for the new 45mm compact gate. It was apparently good for 26psi, it only ever held 24psi for the tune. Since then it has dropped to 19psi on gate pressure so I needed to run boost to the top port.
I had quite the argument with Turbosmart over it, as I wanted to run 30psi off the gate originally, they said their gates aren't up to the task of running that much seat pressure, and they couldn't make me stiffer springs.
My suggestion to anyone about to buy a new gate is to run the 44mm Tial with water cooling. Tial gates hold 4 springs as a bonus, not sure what the maximum pressure is though.