Went for a quicky this A.M. Sadly, I failed "turning on Strava" because I wanted to compare HR's. I'm in Park City, Utah and have been riding here for over 30 years and wanted to get an ebike to reduce my HR on some of these painful climbs. My objectives may change as I get used to the power available, though!
The ride I was on today is 4 miles (4.01) and 1274 feet of climbing, one way to the top. Normally, on my Trance 29er, I'm pushing hard at 90+% max heart rate continuously in 2nd and 3rd gear with a 30t front ring on a 10-51 rear.
I set "Sport" to 100% Support, 30NM Torque and 1 on Launch and kept it there. With a 34t front and the 10-51 rear, I was mostly in 4th and 5th gears and giggling at how civilized the climb was! I think I was pretty much 70-80% max HR by perception the whole way and of course MUCH faster.
I also got some numbers that may help in sizing. My distance from pedal to where my sit bones are on my mountain bike is 33". That's what it is on the Elite 3 as well. I can maybe raise my post half an inch from full down with the stock dropper. The LBS offered to put on a smaller dropper at no charge to help, but if your distance is the same or greater, it should fit. If you put on an SDG Duster saddle, that will gain you a little more.
Using a completely scientifically accurate tape measure, I get 13.6" BB height in low and in high, 14.1". I don't see much reason to run it in high. And, at about 8 mph, the wind over my ears was enough to block out any engine noise. Of course, I'm also pretty deaf.
Nice bike!