Re: towing a trailer
I have some pretty steep grades (8% or more ) around my way and my 08 HCH handles them fine with or without assist (some of the long inclines have drained my pack...).
It'll rip your MPG to shreds, but it'll get up the hill. The "S" mode is great for that. Oddly enough I have found that using cruise control up the hills is kinder to the pack than my foot is, and quite good at the mpg. It does something clever with the CVT and battery pack than I can't mimick with conventional driving.