This topic made me think because I haven't had to do anything caulk wise to my Keystone since I bought it in 2009/2010 model. It's been raining hard for two days so I just went out and checked it for leaks as the slider is and has been out.....
Notta.... But when the rain ceases, I'll be on the ladder checking like I already should have.
As far as warranty and aftermarket warranty, never had much luck getting either of them to do didly squat even with a RV tech calling it in.
Simpler just to do it yourself.