I've been in death valley at 121F for hours at a time outside. So long as you have a hat, hydration and salty snacks it is surprisingly bearable. I would rather have that than even 85F with 100% humidity any day.
Let's look at the data, and use this calculator: https://www.weather.gov/epz/wxcalc_rh
Death Valley: https://forecast.weather.gov/MapClick.php?lat=36.448&lon=-11...
Temperature = 117F.
Humidity = 11%.
Barometric pressure is broken but we'll use the Vegas Int'l airport value: 29.89in. (play with the value, it barely makes a dent).
Plug it in the calc and observe: Wet bulb is 73.69F.
Now we go to Miami: https://forecast.weather.gov/MapClick.php?lat=25.7748&lon=-8...
Temperature = 78F. Humidity = 79%. Barometric pressure: 30.07in
Plug it in the calc and observe: Wet bulb is 73.05F. Not even a degree less.
So yea, as long as I have water I prefer Death Valley.
Does make you wonder, being from Europe I haven't met many people who understand humidity.
Wet heat feels like it's going to wear me down until I collapse. It also feels disgusting to me - I remember leaving my hotel in Manhattan at 4 am when it was 85° and foggy. It felt bad through every one of my senses.
Dry, extreme heat feels like being burned to me. It never felt like it would wear me down as fast (maybe because I grew up with it?), but it felt like my skin might dry up and slough off. And my lungs might dry up as well. I always had nose bleeds because of the dryness.
I think which is worse is quite personal. But "feels like" temps or wet bulb temps don't tell the entire story. They feel completely different to me.
Oh, and I only drive white cars now, even though I no longer live in the desert. My first car was a dark navy blue and that car was brutal when it was 115+°F out. It had A/C, but it couldn't keep up at all. Keeping a white towel in the car was a must because on hot summer days I couldn't touch the steering wheel without the towel if it had been sitting in the sun for any length of time (and there isn't much shade around). When getting out of the car, spread the towel across the seat to keep the seat under 140°F when you return. I didn't get much sympathy from my future wife - neither her car nor her childhood home had A/C.
Now that I live in Phoenix I tell my friends in Belgium: Go bake a cake. Now open the oven when it's on its highest temperature. That's how it feels... for 3 months.
I love it.