Thought I would weigh in on the spring rate conversation. Until recently, I was running the medium spring. The fork felt good, but not great. The 140mm DVO air fork on my 29er felt better, especially on fast, rowdy trails. Obviously not ideal when the trail bike goes downhill better than the enduro bike...
The specific shortcomings I experience on the Ribbon coil with medium spring:
-excessive brake dive
-not using full travel (max of 130mm even when deliberately trying to load the fork on 4'+ drops, rocks, dips, etc)
-felt dead when I wanted to get the front end up
-harsh at high speeds
I tried a bunch of different damper settings, but nothing got the fork quite to where I wanted it. I was on the fence about whether to try the soft spring to see if I could use more travel or try the firm spring to dial out the brake dive and dead feeling.
I went with firm, and I am very, very happy with the results. No more brake dive. No more harshness at speed. No more dead feeling on jumps and trail features. The fork stays higher in its travel, but since I feel more confidence and ride faster, I end up using more travel! 145mm on normal trail rides, about 155mm on faster trails with drops, and 160mm when I purposely land nose heavy. Better fork = faster pace = more travel used.
My current settings
Fork: 27.5 coil at 165mm
Weight: 190lb in gear
Spring: firm
LSC: 2 cicks from closed
Ramp: 20 clicks from closed
Rebound: 10 clicks from closed