The LDSIG is an in-group, and I'm not big on in-groups.
Too little talent with too much of other people's money, as I see it.
This is a topic that periodically comes up on various forums, and it sort of predictably gets locked after a few days (and a few hundred posts!). But until that happens, ~ snip ~.
... One very important benefit is the standards set by NMRA and used by the manufacturers. Without that, our engines and rolling stock may or may not match, digital power systems would be totally incompatible, decoders and electronics unique to one system only, etc., etc. about being a top dog, but about improving your modeling skills to a level you can be proud of and recognized as such. ...