The only models I got to see where a box of Dark Eldar Incubi and a Archon. The Archon was very well done minus a huge about of cleaning up of the flash that needed to be done. Unfortunately the Incubi didn't fair to well, both their weapons and heads where sadly warped. The heads almost to a point that they might not be salvageable.
The material itself is very light and very soft. Which for me means it can be easily converted using basic hobby tools, but will not stand up to well any of the slightest man handling or occasional stray dice. Also make sure your very sure where you wanna glue things.
On the plus side the material unlike forge-world stuff, doesn't need you towash all the crap off of it before you prime it. Its better compared to Privateer Press's material but a little more on the lighter side. It is really good for the smaller detail stuff but I dont expect them to start making the larger vehicles anytime soon with them because they really don't require that much detail and probably wouldn't be very sturdy.
As for the models choices I am kind of irritated at the fact that they decided to start off producing models that already exist. I guess it was easy for them to just reuse their old molds, but I would have liked them to have started off making some stuff that doesn't exist yet. I know there weren't wracks and grotesgues yet, but im sure their would have been plenty of people looking forward to some tyranid kits and some Space Wolfs riding other Space Wolfs.
P.S. Thankfully only few tau stuff has been done and by the time a actual new codex comes out for my beloved little guys, any problems they might have had with this new material are taken care of so their wont be any crappy model kits hiding on the shelves.