Been on Avast for the past couple of years. Zero problems.

I worked as a DJ at a couple radio stations in my early adult-hood. First Class Engineers came and went rather regularly. But, one thing for sure, each new engineer was ALWAYS critical of the previous engineers work and set about changing everything. When it comes to computers, I see the same thing. I'm no expert, but experience has shown me what works and what doesn't. Malwarebytes is highly recommended (I like it) but it is not without its critics. Some love Norton's security programs. I'm not a fan. But if you like it and it works for you....why not? AVG, Avast. Avira...All seem to work just fine. But as stated earlier, use only one anti-virus program.
Eddie

Eddie and friends. I run Malwarebytes after updating. then I run Superantispyware and it gets rid of 4 or 5 things after Malwarebytes had just gotten rid of 4,5,6 things just a short time before. Then I run Advanced Systemcare because it scans and checks the registry, files etc. too, but it does defrag and other things that Malwarebytes or Superantispyware does not do. Then it safely shuts down for the night.

There ya go Boo. No one utility is going to find everything. Super Antispyware will find some things that MWB's will not and vice versa.
Eddie