Curious About Use of Online Resources

Hello everyone,

I am new to this site, but I have some experience in local commercial investments, particularly with multi-family properties. Most of my work in the past has involved personally contacting prospective buyers or sellers, with the use of a personal website for my only online support. I have decided to do the rounds on all of the sites that have discussions about real estate to see what your experiences as an individual have been with using online listing services like Loopnet or CIMLS. There are many residential sites that are well known, but for commercial markets, I only found a few that seem to have large reach. Of the two I just named, they both seem to offer a free service, but I'm wary of spending time to set up accounts if they don't show free listings as often. Has anyone had any luck using any service like theirs? Are their premium options worth the money for the various additional services they provide? What other hidden gems exist out there that I may have missed?

Regards, David