The ROG Strix Z790-E has a heatsink that comes with the motherboard. Assuming you didn't take it off and lose it, you should be fine with the built-in heatsink that comes with your motherboard. Just don't forget to remove the film from the bottom of the heatsink.
I'll be honest, if I were building a computer right now, I would probably get the Firecuda 530. You are unlikely to notice a performance difference with anything Gen 3x4 or above, but the Firecuda is rated for many more writes before going bad, and thus should last longer.