The Perfit Mouse (in 9 left & right hand versions) suits SolidWorks very well from my short time use of the product. [URL]http://www.contourdesign.com[/URL] The Perfit optical mouse works great right out of the box with SolidWorks on WinXP without installing any additional software. 1. Zoom in Solidworks works with the Thumb scroll wheel. 2. The middle finger button does the 3D rotate. (left & right mouse buttons per usual) The lower thumb button needs programming from Contour's driver to be useful and I haven't gotten to that yet. I would say the Perfit is a potential winner for heavy duty 3D solids users, particularly with the range of sizes they have. Would I design it any differently? Yeah, I'ld get rid of the cord & use bluetooth and offer a small version suitable for travel with laptops. My rating: Thumbs up. (no affiliation w/Contouor: nothing but a SWks user). [email][/email]