I'm using FF6.0 now but with very few add ons. It is more stable than 5.0 but ho hum, I did like FF back in the beginning when it was so obviously faster than IE & I could add on a few apps which helped with work & such.
I use Chrome too now with no apps apart from add blocker - simply because it is fast.
I find FF has some issues with Hotmail, I find Chrome & FF have issues with images on some web sites.
The stupidest thing no matter which browser I use - just having one menu button in an unfamiliar place or a bookmark not in the same location just phuqs with my head the my minor OCD; I am a whining child sometimes.