I've been using Solidworks for a couple of years and its really good. It takes a bit of getting use to but once you come up to speed it's fast and intuitive. I use it to draw motorcycle parts to machine on my flat bed mill.
I found this very interesting from the great man. http://wattsupwiththat.com/2012/11/26/another-wuwt-tv-segment-engineer-and-aviation-pioneer-burt-rutan-on-why-he-doubts-global-warming/