avast 6

I've been using Avast 6 for quite a long time. Go ahead and give positive replies to Web Rep prompts unless you have already downloaded and are using SiteAdvisor - it's like SiteAdvisor. If you install Web Rep, you can always disable it or uninstall it later. If you find that some things you are doing get blocked by Avast and the messages asking whether to allow or block become annoying, you may want to uncheck "Monitor the system for unauthorized modifications" in "Expert Settings" for the Behavior Shield.

I don't know which is better. Web Rep is much newer, and only gives you that a lot of people, a few people, or no people recommend the site, and a warning that the site could be dangerous (I think a red symbol instead of green or gray). There are no reviews to look at from other users.

I don't know if the 2 working together could cause a conflict or not. You could try it, and if it seems that your browsing has slowed down noticeably, then you can disable it in the browser plugins or uninstall it from the Avast console.