Hi John, At my impecunious worst, I used my friend's aluminium template to make a copy in acrylate (Perspex). Kind of worked, but too finicky to set up. The thing about templates is that it is surprisingly easy to ding them - just try lifting the router a smidgin before the bit is completely clear of the template (you cannot rely on sound to guide you, as the bit will have completed the cut before it exits the template fingers). Steel fingers might be a bit rough on you dovetail bit under the circumstances- can your friend cut aluminium on his plasma cutter?
What the Milescraft thing does, is to give you a master template, from which one makes any number of working templates, from whatever is to hand - mdf being very suitable because of its dimensional stability.
Have a look at the manual on the Milescraft website - it shows how to make full, spaced and angled dovetails and box joints. You may get some ideas for the new templates you want to design.
Where the Elu jig outshines the Milescraft one, is in half-blind dovetails, where both front/back and side are machined in one pass. But remember which way each must face, and against which side of the jig, otherwise you land up with the equivalent of the apocryphal Aussie submarine, where instead of two matching halves, they built two identical halves - the world's first spoon-shaped submarine.
The Milescraft also cannot make rebated dovetails directly. The work-around is to glue on a false front, after completing the through-dovetails.
Nollaig shona dhuit, and all that sort of thing.