Personal experience from being a McAfee Virus Scan user from versions 4 thru 7 and a McAfee Office 2000 user:
I had a lot of problems with stability on 9x. First with 98se and later on with WinME. Lots of programs locking up, blue screens, general freaky things happening like my taskbar locking up, PC freezing if a .rar file's icon was showing on my screen, random frequent low resource warnings, screen freezes that forced me to hit the reset button, etc. My average uptime on 98se was about 2 hours, uptime on WinME was about 4 hours.
Then one day I decided I wasn't going to pay for upgrading McAfee again. (I was really broke at the time and could hardly afford food, nevermind software).
rkarman told me to install the free
AVG and it was the best thing I ever did. I am so glad I listened to him. All the weird problems went away and my WinME computer became one of the most stable 9x PC's I have ever seen, with uptimes in excess of 3 months, if I can keep my daughter away from it and I don't have a power failure.
Before I switched I thought McAfee was the best antivirus you could get. But experience has taught me otherwise.
But if you still like Mcafee and want a free copy and can't get it from the links given above, another way to do it would be to set up a
free AOL account, even if you don't live in the US, and get the McAfee
antivirus,
firewall, and
antispyware they provide for free. Then you can ditch the AOL software. (keep the account though...the 7 free IMAP email accounts are pretty good and their webmail kicks butt...rivaling Gmail in my opinion, or you can access them with any email client that can handle IMAP)