Originally Posted by
mrhedges
bike parts don't really become obsolete like computers. DA stuff isn't durable either if you want durable go with 105 or ultegra.
I'm afraid you are off-base on that statement. With the possible exception of the cassette D-A is equal or more durable than Ultegra or 105. If you think it's not worth the extra money I can't argue with you, but when compared to the other Shimano groups D-A as a group is as durable as it gets.