I had the demo version of silo awhile back.

got the full version and used it to do a couple of things but got distracted from it.

Lost the program and the zip, serial to it in a hard drive crash.

I searched my email archives and find no sign of my purchase.

And I can't even rwemember the year I bought it...sigh.

But I liked it and wanted to learn more.

Can't afford it now sooooo.

But I'd say if you have the money and want an easy to work with modeler, go for it. :)

Let me introduce you to my multiple personalities. :)
     BluEcho...Faery_Light...Faery_Souls.