Divide rail and stile cuts for easier joints

I've seen two router-bit options for making rail-and-stile joints: matching bit sets and a single combination bit. It seems to me that the matching sets are the better way to go. Any thoughts?
—Greg Perlberg, Chantilly, Va.

We favor the two-bit method, too, Greg. With two-bit sets, you make both cuts with the parts face-down on the router table. When you rout all the pieces face-down, you can sand out minor stock thickness differences from the back, leaving the front profile unaffected.

With a combination bit, though, you rout one profile face-down and the other face-up. Reversing the workpiece orientation this way may require you to sand out stock thickness differences from the front, throwing off the profile at the joints.

Also, with a combination bit like the one shown above, you'll need to take special care to keep hands away from the exposed upper portion of the bit when using the stile-cutting section.