(1) More precise setting of angles (already calibrated);
(2) More secure than many flimsy jigs;
(3) Can use a cup wheel, so get flat surfaces.
(4) Nice smooth slide action and finely calibrated infeed;
(5) Life's too short to make everything (unless making it gives you pleasure or you are short of funds).
Don't know this.
Yes.
See above; using the edge of a disc wheel gives concave faces, using the face to any great extent is not really safe.
david at dlittlewood dot co dot uk
David