SolidWorks supports STL CAD files for 3D printers, so should offer users all the tools they need to successfully convert sldprt to stl.
However, most users that are looking for sldprt to stl conversion actually do not have access to SolidWorks, in which case the situation is a little more tricky. Plenty of programs support SolidWorks formats, yet most of them are commercial and not available for free. Although some sldprt to stl converter online exist, much like is the case with any other web based converter, the results may not be perfect.