I don't have any pictures but yes, I would say it's probably as fast as an MP3 disk navigation interface. It's not too bad, but if you want to scroll through 300 artists, it does get old very fast.
It's nice to have all your music with you in your car at all times, but if you expect to have 4000 songs and be able to just play any random one at any time you will be disappointed.
What I do, I set up 5-10 playlists which are at the top of the list. Then put (on the computer in itunes) some songs you think you would like to listen to in there and use that for the week or so. I keep about 50 songs each in each of those 5-10 play lists which is 300 - 500 songs at my fingertips and name the playlists for different moods: Pop, country, comedy, rock, classic rock, disco, weird... etc. Then on a regular basis I change them around.
The ipod adapter does work rather well. Not as good as the new full speed ones, but the interface is just as intuitive as the ipod itself. Whatever options you see on your ipod, you get on the Z1. Other than the sluggish speed, I think it works great. The full speed ones (like on the D3 from what I heard) is the best, these are the second best integration of an ipod to a head unit that I have ever found.