I am doing them all to the M20 scale, its very helpful in effect to fit a lot on a page, however, owed to the scale, you can easily "upscale" it for printing and such, which is why I do it as "clear" images not fuzzy, so it can easily be resized in MS Paint to 200%, which is a better viewing scale.
www.swdesignalliance.com is where I get the scale and parts from, the forums are more active.