Almost surely I'll return to avast!, especially if 5.1 has a 64bit version. 
What do you mean? avast is fully compatible with x64.
Tech,
I've had my laptop for a little more than a year.
It came with Vista 64. I was eligible for a free upgrade
to 7 64. I requested it and when it came I upgraded to 7 64.
All this time I've had avast! on both computers.
I said all this so you will know I have been aware avast! is fully
compatible with x64. The avast team has repeatedly said
there is little advantage in a x64 version of avast! 5.
I sometimes like to try new softwares.
x64 software catches my eye quicker than x32 programs.
