How is the PHEV on road trips/mountains?

I'm kind of torn between a used XC90 and CX90 PHEV... one thing in the XC90's favor is the ICE is a lot more powerful, so when the battery is depleted on a road trip it can power the car AND charge the battery if I want.

How does the CX90 PHEV do on the highway and in the mountains? We just did a trip in an X5 rental that took us over the Blue Ridge mountains and that I6 absolutely devoured the climbs. It was pretty exquisite actually. But I need 3 rows and want a plug so I think the CX90 and XC90 are my only options. (I looked into Aviator PHEVs and a lot of them have branded titles... I may look again though)