If I'm not mistaken, the carbon fiber tubes used on early models of Inspire were of "woven mesh" type. Late models - including mine - employs so called camo tubes. Accordingly to Clearwater Composites  (http://www.clearwatercomposites.com), US manufacturer of carbon fiber profiles, the tubes in question "... are made with completely different manufacturing processes: "camo" being filament wound (one continuous filament wrapped onto a mandrel), while mesh type is roll-wrapped (each layer of carbon fiber laid up in specific orientation). Roll-wrapped tubes are typically stronger, stiffer, and more consistent than filament wound tubes."

As an engineer with over 50 years of experience I look at my Inspire from slightly different perspective than the majority of this noble society. Undoubtedly the idea of rising arms is of great use for gimbal handling drones and it's designed brilliantly. Unfortunately at the price of rendering very heavy and vulnerable craft, which in case of crash landing usually suffers heavy damage. Analysis of numerous crash reports shows that carbon fiber tubes rarely survive in one piece. Repair or replacement is extremely difficult, if not impossible at all.

To be fair, the change for weaker (cheaper) tubes may be reasoned differently than as a corner-cutting approach. It will be nice to hear from DJI engineering department a word about reasons to implement this change.

I was trying but didn't get the exact explanation about the types of carbon fiber we are using... however the one you call "weaker and cheaper" still perform good in flight and landing

DJI-Tim Posted at 2016-2-24 00:39
I was trying but didn't get the exact explanation about the types of carbon fiber we are using... ho ...

Thank you, Tim. Of course they do perform well in normal flight and landing, but that's not the issue. Should  they break and shatter easily during crash landing (as they usually do), sacrificing themselves in order to protect other, more valuable components of the craft? If that was the idea behind the change, than I rest my case ...

Dobmatt is absolutely right, the first tube model are week and does not capable to resist any chok , my inspire felt from 50 cm hight because of a battery failed and brake the tube. There is any chance to have a tube replacement ?

I guess it's luck of the draw. I bought a V 2.0 T601 in January and got the woven carbon fiber.
Is DJI buying from more than one supplier?

This is real CF arm! Much stronger then the fals one

The problem for me is that when you do break the boom, DJI won't sell you the necessary parts to make the repair.