Does this firm tight top sleep hot?

No, it runs cooler than average for a hybrid. We measured a peak surface temperature in the 29.1 to 31.9 C range, earning an 8.6 out of 10 cooling score. One inch of gel-infused comfort foam pulls heat off the surface while the 800 pocketed coils keep air moving through the core instead of trapping it the way a solid foam slab does. The firm, on-top feel also keeps you from sinking into a heat pocket.