It looks really interesting and very powerful..however, I must say that it is not very user friendly because all these params make it difficult... Too many parameters for a simple tree... and the fact that there is no plant library coming with the product is really annoying... I would expect at least 40-50 trees, bushes and plants ready for our projects...
Even Forestpack that uses simple images of trees has a complete library... and there are many cheap collections out there, some are even freeware....
I visited Onyx site and I find their tree generators a bit expensive but as I've learned each program comes with an extensive library of parameters and you can really make hundreds of trees using them...
I prefer to do everything inside MAX so GrowFX would be great but I really need a good library to start with... I don't have the luxury of spending 3-4 days trying to understand the program.... I would prefer to have 3 weeks and work with the library for my projects at the same time...