Cool, First post in the Kraken Forum The Kraken is a great hot-end, it's the easiest multi-extruder setup I have ever encountered, to calibrate, mount and control. It's also my ONLY hot-end that works really well at high speed with a direct drive extruder. I normally use geared, but for the quad extruder setup, I have opted for direct drive x 4 all in a line. I'll post some photos and files soon. Look out for a review of the Kraken, V4/5 and lots of other hot-ends in the next issue of the RepRapMagazine http://reprapmagazine.com/ (Issue 3) - It covers a year of using various hot-ends in real-world printing on lots of different RepRap machines.
Rich - welcome, we are honoured that you have made the first post! We love The Kraken too. We haven't tried driving it direct, instead we have always used your geared extruder.. (http://www.thingiverse.com/thing:60531) Your talk of direct-drive made me think of Stephen Jensen's post (http://coherent-reprap.blogspot.co.uk/) about his creative direct-drive implementation using a single hobbed bolt and a cam-selector. Looking forward to your reviews of it - there is a lot of shared experience building up out there and it would be great to have it all collated and involve the people that have received theirs in the first shipment.