Wood Duck's faster and more seaworthy. It might be a simpler build, too.

Laszlo

I've been in a similar situation - having built a Skerry and thinking of building a kayak.  

I was also considering the Mill Creek 13 and Wood Duck 12 and had the good fortune to try them both out this past Wednesday.  I thought, as you mentioned, that these boats were similar (stable, easy to get in and out of, more recreational, similar size and weight).

Being in each of these boats was a real eye opener.  Before trying them out I had a preference for the Mill Creek because I really like it's looks.  But I found the Wood Duck to be both more comfortable and easier to control and turn.  I did, however, like the MC 16.5 with two adults in it but for a single the Wood Duck is sweet.

I'd strongly encourage you to find an opportunity to try them out before making a decision.

Well Laz maybe correct about the build if the MC includes a sail rig.  However, if you add a MKIIIWD sail kit to the WD then maybe the course is not so obvious.  Of course you could Cunningham the MC and add hydrofoils; that should add a few design hours – not to mention the debate on seaworthiness.  Or throw in a hybrid deck, or …..

Sorry, couldn’t help myself.

I agree with Bob Santore. Try before you buy.  At CLC's Okume fest last May I tried both the MIll Creek and Wood Duck.  I found the Wood Duck much more responsive and fun to paddle, and in terms of carrying capacity (I have a 65 lb. labrador who likes to come with me) about the same.  I got the Wood Duck 12 kit, spent the next three weeks slathering on epoxy and sanding drips back off, and the finished product (even if a work-boat finish in my inexpert hands) has been a joy.  http://jockyellott.googlepages.com/home