I am familiar with Green Stuff World but was unaware that they branched out into water-slide decals. They have done so with a varied selection of after-market sets that will help you with your next project. (In particular are the three different sets of graffiti art!)
This review concerns itself with their Pin-Up Girls decal set. There are two sheets in the package with twelve different 'girls' depicted along with roundels that could be used separately or as background for the ladies. German and Japanese 'kill markings' are included along with stars and assorted shark-faced bombs.
Each decal, thoughtfully provided in left- and right-hand versions, is printed in three different scales (28mm / 1/58, 32mm/ 1/54, and 54mm/1/32). They are, however, more than adaptable to just about any scale. Color definition and detail is excellent with minimal carrier film.