I sell the LMLM, Profitec Pro 700 and ECM Synchronika, so believe me, my opinion below is unbiased.
There are lots of differences between traditional high end DBs and the LMLM.
Traditional high end DSs:
Ability to use small brew boiler only to save power when using for espresso only.
PID brew temp control
Shot timer (some)
More than enough steam pressure for me.
Fake paddle is a massive disappointment.
LM premium price.
Big steam pressure.
Fast heat up time.
I would say the LMLM is over-rated and over-priced. It's only worth considering if you are going to get Rick's mods. The fact that the factory machine needs after-market mods says a lot.
My opinion. Some people love them. I hope this helps a little.