Very cool - it looks like it serves its purpose well - the concept of Myka's jig is really making it's rounds.
As for comfyfoot's aluminum rails, I personally would be slightly concerned about the router bearing running against aluminum rather than wood - I DID run into a slight problem with mine with the aluminum strips on mine with the bit chomping into it, that was about an inch above the pocket when I came in for my first pass... the bit should have been slightly LOWER so JUST the bearing was on the aluminum. I believe Filippo ended up flipping his rails around because of similar problems. I would also be weary of the strength of those rails to support the weight of a router without getting a bow. I am curious as to whether you actually used this on a guitar or a test piece already??
As with any jig, you should use extreme caution with this, wearing safety glasses, etc. Routers are NOT user-friendly and may not always take kindly to homemade contraptions (like this one).
...Mike
(