I can't cut foam to save my life, there are some places you can have it done but I have never tried them myself. Kits with foam cores are something I enjoy though!! I find them a lot easier then a standard framed wing. I have a lot of lead in my shop so I use that as weight but I tried the vacuum system a few years ago and that can be even better as long as nothing slips unseen when it sucks down. Given a choice these days I would like all the kits to have a foam core wing.