Hi All, I'm always in Econ mode in EV drive because I find it quick enough for city driving and I really don't like worrying about the ICE firing on so easily (Yes, yes, I know some of you can keep the ICE off in Sport but I easily get the ICE firing even in Normal mode!). Typically, during road trips, I just push the HV button and drive (thus, staying in Econ mode/HV). The other day, just for fun, I hit Sport after setting HV and wow, the car is so much more responsive--like night and day. Sure, your mileage will probably take a bit of a hit but if you're mostly cruising, it won't be much. It's just that the power is so much more immediate and linear than in Econ. If the car is already in HV, causing the ICE to run intermittently in all modes, there's really no reason I can think of to stay in Econ or Normal mode. Of course, any power benefits disappear if you've depleted your battery so keep a major charge on it when driving in HV/Sport so it can draw from both the ICE and the battery to maximize horsepower!
Another effect of Econ is reduced intensity of the HVAC. That said, I mostly leave the heat (and AC) off, keep it in Sport mode, and get great EV range (I don't punch the accelerator, and like the nearly-one-foot driving with full regen).
I like to stay in normal so I can use the left paddle for normal braking and not have to undo it with the right paddle.
FWIW, I was in Econ the entire summer with temps in the 90s some weeks and stayed cool as a cucumber. Econ didn’t affect the AC enough to bother me and I like it cold.