I blocked this number on 3/28/2017. These guys are relentless, and have called 15 times. I double-checked 800notes and discovered there was no entry for this number. I gave them a call (not usually a good idea) to see if they were legit. The recorded message said "Hello you've reached the SMG Call Center,. We're unable to take your call right now so please leave a message. If you would like your name removed from the calling list, please state your name, the number that was called, and state that you'd like to be removed from the calling list."

This outfit -- http://www.smgcompany.com/ -- which does have a Call Center, just might be them. Their website brags that they can bring in "leads" using 100s of phone lines, making over 1,000,000 calls per day.

I'm no longer worried that I blocked a number that I shouldn't have.