For web development, I think the Dev tools on FF are getting better, so I'm still using Firebug. I often use both Firefox + Chrome and I don't think one is better then another. I do trust Firefox, comparing with Chrome, the latest looks like a bot, maybe google new web spider ? Well, looks like (Urls magically appearing in their list, etc), not sure.
Firefox and Chrome teams are extremely important, they're bringing new stuff all the time, researching, etc! I wouldn't say their work is bad!
If you can't do better, STFU!
There is one little thing you can do: enable all reporting in Advanced settings if you have not done that yet. Mozilla will get at least some information that might be later used for browser improvements.