I know this is an old thread but we finally JUST got our Ninjaflex. It's been backordered from Lulzbot for about 2 months now. We got their Flexistruder first and were just waiting on the material.

I have to say it was worth the wait! The stuff is VERY rubberlike.

Our first job has been in our store for over a month waiting on this material. It is a seal for a shower fixture diverter valve. The seal is no longer made, and a new valve plus installation would cost the customer over a hundred bucks. We designed the replacement (15 minutes x $40/hr = $10), built it (15 minutes x 20$/hr = $5) and it used $0.08 worth of material. So the customer gets a replacement for $15.08, probably less than what it would cost if the hardware store had them in stock.

Note that the Flexistruder for the Lulzbot TAZ was about $300 and the material is about $60 for 0.75 kg.

Printing notes:

Prints at 230°C
Unheated bed (TAZ uses PE tape covered glass)
30mm/sec
0.4mm layers

It needs to build up pressure inside the nozzle before it extrudes smoothly, but boy does it work well. Bridges decent too, even without the fan running. I am REALLY happy with this stuff. I doubt we could use this with our Makerbots, Type As or Z-Morphs, the Lulzbot TAZ Flexistruder is really key to getting good results, along with the slicing profile they provided for Slic3r.