Originally Posted by Fishy
Is there a big difference from the II to the III?
I have the Simpson II and really like it. The III has the improved cover and zippers (which I ended up upgrading on mine). It also has an improved design for the rainfly and vestibule. The III has better poles and tensioning which doesn't require the lines and stakes to the ground like the II. I haven't had any issue with the panels cracking on mine and it's been on both of my FJ60's, my Hilux and our Tundra more than off.
Here is the ARB Simpson II on my 60. You can see the difference in the vestibule and the lines to the ground which are needed to tension the fly. I've never found them to be an inconvenience.