I have done a lot of Quickwall leaves. You will be pleased with the detail and lack of "bugholes". You can get very thin. While you experiment, try some with and some without the mesh. I like the "without mesh" leaves best if I am working with a small leaf ( sort of a 6 by 8 size or smaller). For the big ones I feel somehow better using the mesh but I don't exactly know if it is necessary. Since you plan on adding the leaves to a background, you could probably get by with no mesh on bigger leaves.
I went outside to take some photos but the camera batteries need recharging so here is what I already had photographed made of Quickwall. It is my yahoo photo album called Quickwall.
Laura

Here is a link that might be useful: try this

Hi,Laura and thanks for the confirmation.My leaves aren't as big,but I'm not using Quickwall but rather my own interpretation of it.I'll prob. use the mesh as these leaves have a lot of lobes that are fairly thin and come to a fine point.I'll be doing smaller leaf mirrors using alder,so no mesh there!
Again,thanks for the input!
Cheers from here

Hi Rick
If you have found Quikwall in BC please let me know where.
I have not been able to source this product.
BTW if you use TUCK tape (the red stuff) to edge your styrofoam molds they will be shiny smooth and last a loooong time.
TUCK tape also works great on wood and metal as a release film.