Dowel joints in plywood
I would use a pocket screw joint.  It is generally considered to be a stronger joint, and you can remove the clamps immediately after driving the screws (as opposed to waiting until the glue sets).  

Along with the strength and speed, it also makes the construction process easier.  You don't have to drill 2 separate holes, and then attempt to get the alignment just right.  You drill the pocket hole in one piece, align the joint, and then drive the screws.  Makes for a more accurate assembly.