When comparing Mac Internet Security X9 vs avast!, the Slant community recommends avast! for most people. In the question“What is the best antivirus software for the Mac OS?” avast! is ranked 4th while Mac Internet Security X9 is ranked 6th.
Ranked in these QuestionsQuestion Ranking
Pros
Pro It's possible to switch between different security profiles based on network
While you are at home, you can use one security profile, and then when connected to public internet it can automatically switch over to a more secure profile.
Pro Many different packages depending on what your specific needs are
If you know what products you need or want it is nice to have the flexibility to buy the software package that has what you need/ want or rather a package that leaves out what you don't want or need for a lower price tag.
Pro Can be set to inform of malware via email
As soon as the software detects malware it can notify you via email.
Pro Detects Windows malware as well
This is useful if you dual-boot into Windows, as this single program covers both operating systems.
Pro Clean and intuitive interface
Pro Decent anti-virus protection
Cons
Con Not available in the App Store
Con Not an all-in-one app
There are a variety of different apps for different security functions and purposes instead of one central application. Not recommended for the non-tech savvy.
Con Pop up window when scanning new disk volumes
Con Takes up a lot of space
This program takes 1.5GB of storage - which is a lot compared to other antiviruses.
Con Tries too hard to sell you the paid version
Con Too noisy
Avast! has sounds turned on by default. It also has a lot of blinky features of questionable use.
Con Makes your system slower than usual
Even though scans are not being run in background, it will slow your system.
Con Opt-out installation of Google Chrome
These advertising tactics are simply unacceptable.
Con Selling potentially identifying user data
Con Detection rate isn't too solid
Avast! is not the sort of antivirus product to give you peace of mind. In practice, it does miss some malware every now and then. You'll need backup virus protection, which raises the question why you should get Avast in the first place.
Con Expires after a year leaving computer exposed to new viruses
Expires and stops updating after a year after which the user's computer may become infected by new viruses not covered by existing patterns.
Con May interfere with hyper-V
Since avast has its own virtualization engine, it will cause issues with hyper-V.
Con Unable to detect some adware such as FADE adware
Con Blocks or causes issues on apps or games
Con "Smart Screen" feature
When running an unknown application, avast will run it wrapped in a sandbox environment first for scanning, then kill the process and re-run it again. A lot of applications do not like this.