Pad Thai is not a traditionally spicy dish, though. It’s a mild street food, so you have to smother it in toppers to get it hot. You’re way better off ordering a spicy curry and asking for a side of chili oil to raise the heat.

To some people, chili oil may as well be ketchup. Thai food uses birds eye chili peppers for heat. Hotter than jalapenos by a lot and a bit hotter than serrano peppers, but generally about half as hot as a habanero and much less hot than scorpion, ghost, reapers, and a few other variants. I can eat all the bird peppers I want on my food. For real heat I add hotter stuff.

Agreed on all counts, but they are excellent choices for growing your own peppers as they produce so many more peppers, and produce or longer, than super hots. I always include at least one of those plants in my garden every year in addition to the super hots.