It is fantastic.
Dura-Ace bar end shifters
Are the 10-speed Dura-Ace bar end shifter compatible with 9-speed drivetrains? If not, what bar end could I use with a 9-speed?
No, but Dura-Ace 9-speed shifters are compatable with Dura-Ace 10-speed drivetrain. If you have 9-speed Dura-Ace stay with Dura-Ace 9-speed shifters.
chucksbikes.com has DA 9S shifters for $60. They would work with 10S if you used the friction mode, but I am doubtful that the indexing is compatible with 10S which MHR seems to be implying.