I've decided to give it a trial
I have no problems with avast but never like to rely on any one piece of software.
Also of course as it is from Microsoft and is free it will, I believe become very popular. I need to be able to comment on this if a client asks so will run it for a week or two and see what happens
First impressions are Good
Install very smooth
Native 64 bit code installed (no *32 in Task manager anyway)
Low memory overhead - highest I've seen is 6100K active and now sat at 640K
CPU overhead is almost non existent in normal use