As long as it doesn't make me start hiccuping. That's when I know it is too hot. Also hate when things are hot just to be annoying and the heat serves no purpose.
This. Each to his own, of course, but jacking up the heat just to jack it up has always struck me as kind of silly. I am also
not a fan of double-ended capsicum extremes (and frankly worry a bit about people who are :whiste

, but that's more a question of whether seeds are included than the heat level itself. Since humans can't digest cellulose, the seeds will get always get you in the end.
I'm also not into making everything spicy. I like spicy food pretty spicy, but I don't for example sprinkle pepper flakes on pizza, and only occasionally use hot sauce on egg-based dishes. And not everything that's supposed to be spicy to one degree or another is supposed to be so spicy that it makes you sweat like you're in a sauna. Mole poblano, f'r instance has only a very mild kick as chile-spicy goes, but it's supposed to be that way. Xnipec on the other hand, is, or should be, pretty damned fiery. Thai penang curry should be only moderately spicy, whereas kaeng pa (aka "jungle") curry, will indeed melt the face off anyone with normal human DNA, the average Thai included.