Alex D - me too. 730mm from BB to saddle rails. I have the legs for a 200mm dropper post, but the seat tube max insertion meant I had to settle on a 150mm dropper. It's as far in as it will go and there's still 75mm of seat post before the bottom of the seal head. AND, if you don't have a dropper, you can only drop it 90mm, assuming you cut the post to min. insertion.
Uphill it's pretty good. I wouldn't say it's fast, since it's a 30 lbs bike, but I have no problem on the tight switchbacks on R&R on Seymour (if your familiar with them). And on my 26" Knolly Endorphin with a steeper HTA I used to struggle and would have to get over friendly with the front of my saddle to clean those. On the Tantrum I just lean forward a bit and spin through them.
There is a very slight bob on steep climbs. The whole camming action of the linkage is less obvious than I thought it would be, but I think that's a good thing. I was actually worried it would do it on descents if I wanted to put in some power, but it thankfully does not. The geometry change and everything is very subtle. Initially I thought it wasn't working, but then I was cleaning all the hard sections on climbs on a 160mm, 65' HTA bike, which is pretty impressive in my books.
Maybe I'll do an amateur review in the forum.