I have "Malwarebytes for MAC" installed and my MacBook Pro and performs well, when I run it. It is FREE.
Malwarebytes, I'm sure, is a tremendous product for taking care of adware, because it subsumed the excellent product Adware Medic. (A product that only looked for adware. It didn't look for any malware whatsoever.)
However, even though Malwarebyte's Web site pays some lip service to dealing with "malware" for the Macintosh, I have strong doubts that it looks for much malware at all. For two reasons.
First, the company doesn't say, what, if any, malware that the product looks for.
Second, the product does a scan, even on a huge hard drive, that is done in seconds. No genuine anti-virus software for the Macintosh is nearly that fast when doing a full search. I can only assume that's because a through search for everything that might be present simply requires some time. Malwarebytes doesn't do such a search.
It's nice that Malwarebytes is free, and it's nice that it is a great anti-adware product. But I wouldn't put any faith at all in it doing anything for actual malware.