There are plenty more free trials around such as ESET, Bitdefender etc. if you wish to utilize these different trials make sure you completely uninstall the previous anti-virus as it might conflict with the new one.
just use free.avg.com and get that instead. if you dont trust the promotion site that avg uses. Simple yet profound
360 use 360 internet security , latest version . Very light and feature rich. Do a bit of study on it and you'll be amazed by the outcome.