I haven't, but recently purchased a used LL2 and in the process of researching it I exchanged with several LL2 owners who mentioned looking into the LL2.1 and concluding the differences were not in sound. I recall a gain switch for reducing the overall gain if needed, and a connector to automatically power up a Lamm amp if connected to the pre. Then the obvious aesthetics changes.
My 0.5 cents :-)
My 0.5 cents :-)