It's worth it to me to buy the DVDs. I can use the trees in Poser as well as Vue.

And I'm not sure I'll ever become a good modeller with XFrog (though I'll certainly give it a shot). Even if I do become an expert plant modeller, there's the problem of textures. Just taking photos in your backyard won't necessarily provide the quality you need to make realistic textures. And even if it does, what about plants that don't grow where you live? I want tropical plants, but I'm in upstate New York.