I love the 681, it was great being back in it and brings back a lot of great memories. I also love the 840 as it is a nice upgrade from the 681.
I might be stating the obvious, but i really like the Collins 106 over the H14. I thought the G600TXI is pretty neat as i have never flown in one before, maybe some day if i save enough pennies, however, our existing setup in the 840 is nice and it works well currently, so i am not sure i would do that until something fails in it? We have a few tweaks we need to do with the GPSS steering and the Collins yet, but i am very happy with this autopilot and i love the altitude preselect feature also.
But it was a great weekend meeting and seeing everyone, i wish i could have brought some of the warmth back home though, i tried, but it didnt work.