I was a bit sceptical about the cat tower, given the sheer amount of dodgy re-sellers and drop-shippers there are with these sort of things.
But this is legit! The customer service was very good (just through the chat thing on the website) and although a single panel had snapped in transit, they were very quick to send a replacement.
The tower came in a few days (3 or so) and the replacement panel came slower (10ish days).
Very easy to build if you've ever made anything from Ikea. And it all fits together extremely well. I can't speak for the other towers, but the hexagon is extremely robust and the cats were quick to explore it and now use it in a room where there isn't an easy way to otherwise look out the window.
Couldn't recommend enough! Great quality, great price, good returns/refund policy, good communication - and if you like the wooden modern design then there doesn't seem to be anything even remotely as good in Australia. I'll revisit PetOMG before going elsewhere if I need another tower.