Is Supertramp a really bad band or just very underrated?

I "found" this band a few months ago when a friend of mine gave me a cd of theirs named Breakfast in America. I loved it and wanted to find out more, to my surprise i couldnt find much on them except a biography on wikipedia..... And well....i went to youtube and tried to look up their videos....just found live videos. anyhow the few stuff that i found was that they were a "one-hit wonder"......and that was about it. i honestly thought they were a lot more than that. so why it isnt as recognized as ummm nirvana or foreigner at the very least? just wondering.