I have used SolidWorks 2003<5yrs>, Inventor<6mos>, SolidEdge<demo copy>, SDRC<3yrs>, and currently use Pro/E 2001<2yrs>.
I favor SolidWorks because the ease of use and functionality is built in without needing to buy extensions. But like most software packages they do have limitations. For Example, If I were doing complex surfacing I would go with Pro/E 2001 or CATIA. Although, SolidWorks has come along way since the early days and has become a key player in the highend CAD market.
But after spending two solid years with Pro/E 14, 2000^2 and 2001 I really like it's functionality. Although, I refuse to upgrade to Wildfire, like Ben said "Wildfires are dangerous, hard to control, and economically catastrophic." PTC, needs to rethink Wildfire's direction in industry because from what I see and read it looks like a version of SolidWorks.
I personally would stay away from Inventor. I stumbled across Inventor because I was helping a friend complete a project and his customer wanted it modeled in Inventor. That was six months of hell, Inventor, in my humble CAD opinion is two years behind the curve.
I guess the bottom line is ask the reps hard questions and stay away from those cook-book demos. Trust me I use to be a Pro/E demo Jockey....canned demos will not give you a feel. Do a thirty day eval from each software company. Best of Luck
Vince