I have the 6600 and i love her.
BUT if you sew garments, it doesn't have the "free arm". i don't believe the 11000 does either.
this was not an issue for me. and i also own the janome platinum, and it does, if i were to ever use it. it is my travel and class machine..12 pounds.
you can go to the Janome website and do a side by side comparison.
all 3 are Heavy,around 25 pounds.
i would love to have more than a 9 inch throat....but i won't trade the 6600 for any machine.