Except for a few odd gravers, I use Lindsay templates for most of my sharpening. You can't go wrong with them, simple to use, and they work well every time.
I use them, and I use my Dual Angle. While you can do anything on the Dual Angle you can do with a template, there are quite a few of the points that are a heck of a lot easier to do with the templates.
The Dual Angle is infinitely flexible while the templates are pretty much locked to what they're meant to do. You can vary the face angle by varying the height of the stone and/or the distance the graver extends from the holder.
But then again, with the templates you always get the exact same angle on each facet - that's nearly impossible with the Dual Angle.
Two tips I have learned that help a lot using the Templates.
1) Mark which side of the graver blank is 'up' when you put it in the holder (by 'up' I mean aligned with the notch/set screw). I started this after I went nuts trying to figure out how one of Carl's gravers should orient for re-sharpening. I use a diamond file to make a mark.
2) When shaping a new graver, do the face first, then go to the smaller shaping template (if there is one). I learned this when I made my first flat graver 'upside down'. Knowing where the face is helps you see how the point will develop.
each sharpening system does a great job. the dual angle by grs can make most any geometry needed. the lindsay is a bit easier to master. except for the face angle, you need a separate template for each graver-- 70, 90, 110, 116, 120. if you only want one system, i'd advise the grs dual angle. in the long run, it's more versatile.