[rb67]

Wow sketchup looks really great! It looks really well made and really easy to use. That is probably your best bet. I've had experience with some professional suites (UniGraphics, Catia, I-Deas) and I have to say, for something quick and easy, you should probably avoid the professional suites. Well, I-Deas is OK, but you're much better off with sketchup from the way it looks.

 

[patman657]

SolidWorks is the most intuitive pro software I have used, but it also costs about $4000. If you can get the student version, it is less than $200 for what I believe is the same package as the pro version and includes the COSMOSWorks package for stress testing. The included rendering engine is quite weak, however. Don't expect anything close to photorealism, if that is important to you. I render with V-Ray in conjunction with 3DS Max, but that will run you about another four grand. With little exception, good CAD software comes at a high price.

 

[fabool]

MoI might suffice. It's also free (beta), so it doesn't hurt to try.