Ive had the 2016 for a few years and as long as you have an 11 speed it climbs pretty good, personally never lock it out. The 2018 feels a lot like a tank, but has eagle so it does climb a lot better.
I've had both of the suspension platforms a 2015 and a 2018
they both climb ok enough to get me to the top for my descents. If you prioritize climbing over descending a 153 wouldn't be my choice probably. They are not light weight bikes is one thing against them. The 2015 has a lot more bob in it than the 2018 platform, the 2018 def is a big step up in pedaling from the '15 design, has a lot to do with the redesigned suspension curve and really helps control the bobbing sensation when pedaling
so yeah the 2018 does a lot better than the previous design as far as pedaling but its def not a strong suit for these bikes.