I'm an older guy, and have always bought GM vehicles, and nothing else. Never owned another brand. My dad worked for GM and retired after more than 35 years of service. He'd turn over in his grave if he knew I bought something other than GM.
That said, it has been my experience in the past that GM will not fix or repair anything under warranty until it breaks completely. The only exception is if it a recall or they (the GM dealer) get a service bulletin about a particular problem or possible problem; otherwise, it is usually "normal operation".
But I still keep buying GM products, for better or worse... maybe the good outweighs the bad? Or, maybe it is just respect for my late dad, I'm not sure.