I'll bet it will be the most popular for quite a time.
It's the 50+ equivalent of the Terrier – that is a pretty popular boat. Ideal for a young lad…
How long until someone makes a 40" version?
I'm pretty sure it will need a bit of internal re-design at 40"!
At 20" the boat is 1:48 scale, and there is an Eduard set of US Naval Personnel at just this scale. You can see one on the boat. Usually, EeZeBilts are intended to be cheap and use household items for fittings where possible (you can see felt-tip tops as cannon mountings) but that Eduard set is cheap enough to include as a justifiable extra…
Interestingly, if you print out the plans on A3, as a lot of people do, you get a boat 1.4x the design size, at 28". This turns out to be at 1:35 scale, which is another standard size, and Italeri do a PT 109 Personnel set at that scale, as well as a 'weapons and trim' set. But here we are rather losing the 'cheap beginner' ethos… 
Edited By Dodgy Geezer on 17/01/2015 01:29:01
Edited By Dodgy Geezer on 17/01/2015 01:31:40