Chad,
Biggest thing is people want a bigger and more scale model. And most de Havilland nut do not like the long nose version but is easy to modify. Biggest comments are that while it looks like a TO it is a squared off verion and actually was done that way to be a easy building bird.
I do have the building manual on-line in PDF format in the "support" section. So you can see just how it builds.
It was designed as an easy building bird there are several comments on this one over on E zone.com do a serch for Twin Otter but here is one thread on it. Several others have been done over there as well.
http://www.rcgroups.com/forums/showthread.php?t=230083&highlight=Twin+Otter
That one was done as a short nose and built from plans.....I sell kits or I do have plans for those who like to build from them.
Thanks, Mark Turner
http://www.rtmodels.com