We did South San Jose to Santa Cruz (Seaside & Bay) and back today over highway 17 (1800 feet elevation at the summit) with no problem. We started with 100% charge and got back home with 3 bars and 24 miles remaining range. Total distance covered was 72.8 miles. We trickle charged (L1) at our destination for a few hours which gave us 1 bar back, but we got there with 7 bars bars remaining so we could have made it home without it. Route was highways 85 & 17 and speed was 55-60, dropping to 50 on the section of 17 where the speed limit is 50. A/C was on for the trip over and off for the trip back. We had 2 adults and one 18-month old on board.
We averaged 5.0 miles/kWh on the way over and 4.6 on the way back (per the dash). I reset at the summit on the way over just to see the difference. We got 3.0 miles/kWh on the way up and 8.0 on the way down. Remaining range at the summit was only 34 miles (we still had 51 miles to go to get to our destination and back home!), but by the time we reached Santa Cruz it had climbed to 64. We didn't lose any bars on the way down, but we didn't get any back either despite lots of regen.
I noticed that the dash miles/kWh pegged at 8.0 on the way down the hill to Santa Cruz, but the center console miles/kWh was 18.2 (both were reset at the summit). When I combine the uphill segment with the downhill segment, weighted by the distance of each leg, I get (22.1/36.9)*3.1+(14.8/36.9)*18.2=9.2 using the center console numbers, but (22.1/36.9)*3.0+(14.8/36.9)*8.0=5.0 using the dash numbers. 5.0 seems closer to reality and more in line with my 4.6 number coming home (I didn't reset at the summit on the way back), but the 8.0 number seems low considering that it held at 8.0 for a while despite the fact that the downhill leg was mostly regen. Something funky going on there.
Here's the elevation profile: