Coming up on 13 years for me next March.
I've learned that there hasn't been a question that I've had that someone online couldn't answer. Sort of my trainapedia!
I've also watched a lot of folks come and a lot of folks go, some in a huff!
The knowledge on this site, not just for Lionel, K-line, MTH, etc, but the lesser known trains like KMT, Weaver, etc is outstanding!