Zu Druid upgrade kit


I have a pre 2008 Druid and am thinking about upgrading it with the Zu upgrade kit (now available upon request at approx. 650$)and wonder whether this is a sensible proposition. How does the upgrade model compare to the pre-08 version and would you recommend this route as a short-term upgrade or rather save for another model such as the Essence?

I am looking at the Essence(moving from Klipsch RF-7) i listen to lots of singer songwriter Dylan, David Gray, Damien Rice and classic rock Beatles, Floyd, etc. How would the Essence work with this type of music? I like the RF-7s but feel like they can sound somewhat hollow at times. The presentation is up front, which I like but I feel like i am missing some midrange tone.
They work well with all kinds of music. I too listen to singer song writer stuff, along with acoustic, and they sound great. They also sound great with hard rock and metal too.
Thank you, that has been very helpful. May I ask which amp you are running on the Essence (and have used on the Druid)?
I was using a Nuforce IA-7 integrated on both the Druid and the Essence. Now have swithced over to a Cayin A-50T tube amp with the Gold Lion KT-77 tubes. This amp is soooooo sweet with the Gold Lions. It can be found under 1K used here on Audiogon. Nice match with the Zu's.
The Essence is a killer. Love it with all sorts of music- jazz, classical, rock. It's a great all around performer.