I fooled around with Bonzai for a bit. Only when it was in Beta (I didnt like that the earlier betas were less refined, but thats kindof more normal for betas.) I also didnt put a great effort into it, so thats a grain of salt for my comments.

For me, it blurred the line of poly and NURBS too much. I would prefer to be in one or the other. I never was really sure what I was working with.

They have some advanced tools. Some that I was really after, but the export wasnt always going to other apps properly. The really fancy blends were creating some faulty geometry (Only in other apps. It wasnt apparent in the Z's) I wonder what kernel they use? Possibly proprietary or ACIS based? It's NURBS surface modification tools are insane (powerful). I didnt get to the point of testing if they work on geometry brought in, as opposed to native creation.

Most of the stuff to really make it work, was deeper in dialogues so would have taken some time on the curve to figure out how/when/what/why. For me, it was along the lines of Rhino (For me, worse). The "it's better than Rhino" was not true, for me.

I just stopped early, because i wasnt confident ( Rememeber, I didnt put much time or effort)

If someone could put the time in to really push it (either the light or full versions) it would propbably prove to be pretty good. You may want to look at the userbase/community to see if the type of support for becoming proficient suits you.

There are several things in it I would like to see in MoI, and would have bought it for those, but shyed away for the above.