good idea, but must be done tactfully, or else you run the risk of being labeled as that geeky kid who always insists on disrupting the status quo. remember, for a lot of people, web browsers are interchangeable, so if they're happy with X and you switch them to Y, then they'll be strictly more mad. however, if they're fed up with how X is too slow or buggy and you show them Y, then they're more likely to be appreciative.