My .02....Just getting started.......Husqvarna Swedish Roller Guide.Comes for .325 and 3/8th chain.
The kit is inexpensive around 15 bucks. Comes with guide, correct size round files, file handle, and raker file. Very simple to use and you get very good results.PLUS, the raker depth gauge is a progressive one. There has been a lot of discussion on this regarding this method as a more accurate way vs the gauge that lays across a few teeth or putting a flat edge across the cutters.
Here's a video from Husqvarna demonstrating it.
This is my "in-shop" setup for using it.This is my 394 with a 32" bar. I use a paint pen to mark a tooth as starting point reference. I can crank this one out in about 15 minutes.
My in field setup. 7900 with 24" bar and I was getting it done in 5 min per side.
Really no reason to have a dull chain in the field any more when you can touch it up quickly.
A few lessons, I have learned. Pay attention to stroke count and do same amount per cutter. Every now and then I get "shiny objected" and wind up with a short tooth. lol
I would start with a new chain, that way you are starting with a clean slate, and the angles a correct for a point of reference.
I like good files and stick to Pferd's or Save Edge's.Maybe explore that option once you burn up ones that come with the kit.
The file will let you know what's going on. Big difference in feel between a good cut going on and chattering.Light pressure and let the file do the work. It took me a while to figure this one out. lol
Good luck and take your time.