Should a classic car lover be required to love every version of his favorite car to qualify as a true car lover? For example, the Ford Mustang changed its look drastically in the 70's, but has since returned to the older look and feel. Should the 60's Mustang lovers be required to like the 70's, 80's and 90's versions of the Mustang in order to be a true Mustang fan? I think not.
I think that the battles between singer fans should be a separate topic, and not be associated with being a "true fan" of a specific band. Just because you didn't like Steve Augeri singing for Journey doesn't mean you are not a true Journey fan anymore than being a true U.S. patriot requires you to love George W. Bush. I personally have no good memories of Steve Augeri singing for Journey, but I am still one of the biggest Journey fans on the planet. I may never support Journey replacing Steve Perry with anyone - but I still love Journey. They are a permanent part of my music collection and are my all-time favorite band next to Rush (only because I'm a drummer - Neil Peart is da man!). But that shouldn't mean that I have to worship their newest lead singer, or the last one, or the one before that.

