I don’t use Safari (much) because it doesn’t “pin” tabs. I often have a lot of tabs open, and pinning high-use tabs is helpful.
I don’t use Internet Explorer (much) because I run on Mac and Windows, and there is no (recent) IE for Mac.
I use Chrome instead of Firefox because the Chrome edition of AdBlock allows me to select individual page elements and block them. The Firefox AdBlock (from the same developer) doesn’t support this. I use it on many sites, to remove distractions – not just things which are ads, strictly speaking. Yes, the AdBlock feature list determines which browser I use. There is just so much distraction on most web pages that I consider AdBlock essential.
Note that I for sites I like a lot, I will un-block some ads, so that the provider get his/her ad revenue.
There are a few sites that have bugs when run in Chrome. I really wish there were an extension which would automatically move a site in Chrome to Firefox. Note that I know there are several ways for me to ‘conveniently’ move a site from Chrome to Firefox. The effort of the move isn’t the issue. The issue is that I don’t want to have to remember which sites have to be moved to Firefox. I want the extension to remember and auto-move. The closest I can come to this now is to use Note Anywhere to put a post-it on web sites that don’t work in Chrome, telling me to reopen the site. Ugh!