Well, I got some help from some friends and we set up the hicat late last week, so my cats have had a few days to enjoy it so far. It's been a pretty big hit, thankfully. When I'm in the livingroom the hicat is definitely a buzz of activity.
First some of the particulars:
It's covered with this really heavy-duty tightly wound material, that the cats seem to climb really well. And it seems to wear really well too as the cats haven't even put a dent in it yet whatsoever.
My hicat is one attached to the wall rather than the ceiling (floor to ceiling is actually their "default" install). The advantage of the wall install is that you don't have to be as carefully about measuring everything to the millimeter, and if you need to move the hicat to a different place in the house (with a different ceiling height) you can do that. The wall install is very sturdy also. 3 adult cats jumping and climbing up and down that thing and it doesn't budge!
Now that I've had it a while though I can see that actually the biggest benefit to the wall installed hicat is that you can get it with an extra perch at the very top. And that of course is where all my cats want to head for and hang out (and play).
I have what's called a "fat tom" in that it is wider in diameter than the basic hicats. In hindsight I think that was a good choice, as it gives the cats a bit more room to mess around inside it.
http://www.jeppie.net/cats/hicat/serafina_neytiri3.jpg[/img]
There is two different ways to configure each of the main holes in it:
A full perch (with catbed option, which is custom made to perfectly fit the perch)
[img]http://www.jeppie.net/cats/hicat/catbed_internal.jpg
or as a "wormhole"
The wormhole is a perch with a big hole in it, so that the cats can climb the hicat "internally" and climb up and down through the perches.
As usual though, the cats never quite seem to use it as you expect
My cats mostly like to either sit on the top perch, or the connector against the wall, or just climbing up and down the exterior.
I also got an optional toy for it, which is a band of velcro with little darts that stick to it. That's actually been a huge hit with the cats. They immediately sprint up the tree when I throw one up there, and start batting down the darts.