The inside of the PC6089 is polished aluminum, which although nice and shiny, lends itself to fingerprinting quite well. If you are pedantic about cleanliness, you'll find yourself polishing the inside following every time you work on it.
The lower 3.5" bays are mounted vertically, and are completely removable. They are also quite excellently situated right behind the two intake fans at the front. This is great for keeping those 7200RPM drive cool!
The upper 3.5" bays are all externally accessible, for your floppy/zip etc.
The motherboard tray is removable via thumbscrews and hopefully makes it easier to assemble your beloved beast. Lian Li uses little pop in clips for standoffs rather than the more common brass screw-in type. The front panel connectors have a little joiner in the middle so that you can remove the motherboard tray without having to reconnect all of your LEDs and such on the motherboard headers.
The front USB headers all have individual connectors to connect to the motherboard. You need to know the pinouts for your mainboard here, otherwise bad things could happen to your USB devices. Interestingly, unlike the front panel header, these don't have the connector later on in the chain, so if you have the front USB's hooked up you will have to disconnect them to remove the motherboard tray.
Here is the 80mm rear exhaust fan, with its 3-pin motherboard header. The top blowhole uses a pass through Molex setup.
The front intake fans are behind the lower 3.5" bays. These are speed controlled via a switch on the front bezel and powered via Molex pass through.
Other models have a large filter between the fans and the front bezel, but the PC6089 only has a very small foam filter in the bottom. This will need to be cleaned often if you are in a dusty environment or keep your tower on the floor.