Despite the name, it is not as hot as you might expect: someone used to hot stuff should be able to taste a teaspoon of this stuff and enjoy a nice lasting burning sensation equally distributed throughout the mouth and the tongue, and swallow it without any harsh feeling in the throat. Those who eat habaneros like peanuts won't find it particularly hot; there are many sauces out there a lot hotter than this. Of course, who are not used to strong chili sauces should go easy to begin with, because it is hotter than most of the stuff you can buy in a normal supermarket.
The good thing about the sauce is the flavour; it is not just about being hot, but also enjoying the taste. I can't speak for everybody, but to me, it has a very nice balance of ingredients: the typical taste of the habaneros is definitely there, not too salty, with a hint of tomato, garlic and a bit fruity, but not too much (I don't buy sauces with added sugar or too sweet). It goes really well with kebabs, sausages, burgers... or any meaty stuff where you want to pour a chilli sauce straight over it.