: My question to the WH40k fans out there is this: Do these transfers need to
: be on a perfectly level surface, or can they be used on a curved / rough
: surface?
They can work on a curved surface, so long as you use a craft knife (Xacto or similar is best) to make a small slit in the transfer; this allows the decal to sit flush to the surface without bunching or bubbling.
They might adhere to a rough surface, but they'd look frosted afterwards because of the air pockets trapped underneath. The solution for this is to apply clear gloss varnish (and allowing it to dry!) on the surface before putting the decal on; this creates a smooth surface for the decal to adhere to.
Of course, after putting on a water-slide transfer you MUST put on a fixative coating to prevent the transfer from tearing or simply dissolving off. They're unfortunately sensitive to things like sweat and finger oils. GW sells "Purity Seal" varnish in spray cans which provides a very durable gloss finish; if you want a more realistic matte finish, you can go with Krylon fixative (found in craft stores) as I do.
: Man o' man, I'd love to get some quasi-UESC symbols put on some random
: soldier figures and one of my many Master Chief figures. LoL. Seriously
: though: Could these Warhammer transfers work on conventional plastic
: figures? (Without ripping off if I handel it?)
See above for the handling... the only other possible fly in the ointment is if the figures are made from flexible plastic. If the figures tend to flex, then the sealant and the decals are at risk. They should still be alright if handled gently.
-- Steve has learned many of these lessons from painful experience.