I have daily access to AutoDesk Inventor 10 & SolidWorks 2005, but my preference for solid modeling is AutoDesk's Mechanical Desktop.
I don't want seperate (linked part files). I'm not concerned with parametric features & I don't want constraints.
What I want is to be able to be able to work within (1) drawing, without limitations.
I've been working with AutoCad since '89, starting with Release 9 on DOS. The funny & misunderstood thing about AutoCAD, repeated to me over & over was that it couldn't do 3D, but I was creating 3D on R12 DOS!!!
Mechanical Desktop allows the user to choose whether they want to work in (1) main drawing, like I do, or set it up so individual parts files are assembled in a separate assembly file.
That's what I like, a choice! Inventor & SolidWorks don't give you that option.