I don't know if any tomato is more "hard to kill" than others, but hot weather tomatoes is a frequent topic on the tomato foum, but of course most of those people live where their experience is heat = humidity, so their answers really don't apply to our weather.
Here is my list from 13 years of growing in Sacramento:

Large varieties for hot weather (above 100 degrees):

Mexico, Giant Belgium, Stump of the World, Marianna's Peace, Big Beef, Brandy Boy, Boondocks

Medium varieties: Stupice, Jetsetter, Arkansas Traveler, Burgundy Traveler, Manalucie, Moskvich, Orange Russian 117 (altough these can grow to beefsteak size), Peron, Jubilee, Heidi

and

just about all cherry/grape tomatoes.

And FYI I have found that it does help with fruit set if you shade them in the hottest part of the day, and hose them down with cool water when the humidity is low.