I own the same printing equipment as Ralle Schneider of tailormade decals does (however i am operating it on "home use basis" ), and am having absolutely no problems whatsoever with transparency issues. Even fine white stencils come out absolutely white on black underground without showing through, see for yourself:



I do not know with what settings he is operating his stuff...with the ones i am using, things definetly do not shine through.
If you want i can print some up for you to try...

Regards
Hank