Anyone who thinks they only had one great album is totally overlooking the 1975 self-titled album (the first one with Lindsay Buckingham and Stevie Nicks - often referred to as the white album). Rumours had the monster hits, but in many ways,the white album was a "better" album that showed off the bands individual talents to a greater degree.
I saw them live five years ago and they put on a tremendous show. The highlight of the show was I'm so Afraid, which has always been a staple of their live performances. Lindsay Buckingham was not just the lead guitarist on so many of their most well known songs, he was also their only male vocalist from the mid-70s to the mid-80s - the height of their popularity. Even if they hire two great guitarists to replace him, I can't imagine anyone else singing the lead vocals on I'm so Afraid, Don't Stop, Go Your Own Way, The Chain, etc.
I'm very glad I saw them live when I did.