I have been using the Free version for years now and to all appearances it does what it says on the tin. I have not had reason to change to a paid-for alternative (Avast or anyone else). I have a separate Firewall (Comodo - which has been experiencing some problems recently). I did however take up Avast's offer of a 60 day free trial of the Premium software ("what is there to lose?") but cancelled before the deadline.
Since when I have been bombarded with pop-ups urging me to upgrade - which whilst irritating I have ignored ... until it turned out that the little Avast icon at the bottom right hand corner of the screen said that I was "unprotected". Obviously I had to take this seriously and checked in the W7 Action Centre, but this indicated that Avast AV protection was still in place.
Neither Avast nor anyone else is under any obligation to provide free software to users like me, and as a freebie user I have few rights to demand anything in return. Except that if Avast takes steps to create the (false???) impression that the free protection that I had enjoyed in the past had now been discontinued unless I paid for the upgrade - to me this amounts to unethical heavy handed tactics. I am faced with the uncertainty from the conflict of messages. If using the frighteners to force users like me to upgrade is Avast's policy I will upgrade - but to Kaspersky not to Avast.
Before making a decision I would welcome comments (for or against) and advice from other forum members. Tks