I cut sticky pine trees and less sticky birch trees with .325 Oregon 21BPX chain that I did sharpen with help of Husky roller file guide and depth gauge combination.
Got my hands messed with pine sap and nice long chips when cutting rounds off from the logs.
I did set rakers with "soft" slot in Husky depth gauge tool, chain did cut quite well and I think it became better after few cuts.
Somehow manage to keep my chain sharp when I stack logs to holder thing I welded together from old rusted pipes, but sometimes without any sensible reason I try to cut those pipes with the chainsaw and it does not do any good to my chain, I wonder why is that...