Yes it is, here's the link to the website:
http://www.redseamax.com/redseamax/index.html
They certainly have their pros and cons but I have one (first marine tank) and am happy with the decision to get it....... of course the next tank will be a different story....!
Loopy, when I set mine up I played around in the shop with bits of rock to get a structure I was happy with and then took photos so I could replicate it later. Probably looked a bit odd for the other customers come to think of it! You can break it but it tends to crumble and not break exactly in the way you want (well at least for me) so I found it easier to use a couple of larger pieces for the basic structure and then use smaller bits to get the effects I was after like tunnels etc