I have almost all of the different file guide except for the Pferd or Stihl models that knock down the rakers (depth gauge) at the same time as you are sharpening the cutters.
I use the bar mount type the least of any but I am generally too impatient to set it up correctly. I have at least four different versions, one is Oregon, one is like the Oregon but painted yellow, the most recent one I received is a vintage model manufactured by Pakard in Des Moines, IA, and I have a couple of the McCulloch version of the bar mount "File N Joint" models as well.
I also have the Husqvarna roller guides for .325 and 3/8" but find they don't really fit or work well with every different chain. Understand I have a lot of different chains from collecting saws, many of which are not currently being manufactured.
I also have several different sizes of a Windsor roller guide, they work pretty well on semi-chisel chain as they were designed specifically for the semi-chisel cutters. I like the look and feel of the Windsor better than the Husky guides.
I also have several different types of file mounted guides, one I will call the "flat" guide that controls the depth of the cut, another I call the "V" guides, and lastly the round guides. The flat and the V do a pretty good job of controlling the depth of the cut and have some machine marks to help with the top plate angle. I do use the V guides extensively on 1/2" and larger pitch chains and they work pretty well, keep in mind that you have a large cutter so it is easier to see what you are doing. I really like the round guides as I can manipulate them to control the depth of the file in the tooth and achieve much more consistent results that when I try to file free hand. Still you have to watch all of the angle simultaneously.
In my opinion, the Carlton File-O-Plates were the best file guides ever made, they come in chipper, semi-chisel, and chisel design to fit the different chain styles, positively control the depth of the file so you don't get too much hook. You can use a smaller file if you need towards the end of the cutter life when the overall height of the tooth is reduced or for making a particularly "fast" chain that won't hold an edge quite as well. The only drawback I find with the File-O-Plates is that I tend to press the file pretty hard against the plate and dull my file too quickly. I won't get too deep into the debate over the "progressive" reduction in the raker/depth gauge height but the depth gauge on the File-O-Plate works very well.
I also have a Carlton grinder that I use for chains that are really rough, I ended up getting two of the CBN wheels 1/8" for .325 and LP chain, 3/16" for regular 3/8" and .404 chain. I did modify the grinder to make the motor reversible so I can always grind into the tooth on both left and right hand cutters.
I don't (yet) have one of the Timberline rigs that use a carbide cutter but I have seen one used on a modern chisel chain and the results were pretty impressive. If all I had was one size chisel chain, I think the Timberline would be a good investment.
At the end of the day, your first step should be to have a selection of quality files on hand and know when to toss them out. Second step is to make sure you can hold the chain positively when filing, if the bar is in good condition I can over tension the chain and clamp one end in the vise while filing, if the bar is too sloppy for that I have a Homelite 410 chain vise that will hold them perfectly still. With a good selection of sharp files, the chain held firmly, and good lighting any of the guides can produce good results if used properly.
When you break in a new file, go gently with it. Think of the teeth on the file like the point on a newly sharpened pencil...a bit a careful use and the tip will hold an edge very well. Excessive pressure at the start will chip the sharp edge and it will never work as well as it could. Not all files are created equal either so when you find one that works well and lasts a long time, try to stick with that brand. Some will suggest 1 to 6 chains and the file is finished but a lot depends on the condition of the chain when you start and how you treat your file(s). Try to prevent files from clattering around in a tool box or workbench drawer, wrap them in a rag or protect them with soda straws to keep them in the best shape.
One final note, I do keep a few of those Dremel type tools and cutters on hand. From time to time you will encounter a chain that has been severely "rocked" and you don't want to spend the time and waste a file on getting those teeth back into shape.
Mark