I have to side with LoweBow on this one. I used to be a big proponent of the FMJ's, but after another year of experience with them I do not think they are as durable as normal Axis shafts (both 340's and 300's). I've still got some but would gladly trade them in a heartbeat for the discontinued Beman MFX Max4 shafts...now THOSE were a tough small diameter shaft. Also, unlike all carbon shafts, the aluminum shell will bend and create a slightly bent but not necessarily broken shaft as a result. Carbon's "straight or broke" characteristic is very valuable to me. FMJ's do work great at not mushrooming up near the point as other not footed carbons do...they just seem to be more fragile everywhere else to me.
I have been shooting the Nano's out of my backup bow and the jury is still out for final judgement but they might end up being more durable than the standard Axis type shafts. If I had to pick a new shaft, I'd personally look at these first.