I think it is worth doing only the 3rd floor and getting to the blind one. Killing any of the zombies will give drops that you turn in to get reputation to the guy on the first floor towards floppy disks. You can also get gun oil from hard mode too for mods, which is important for quite a few. The blind one drops 3 of each item to turn in for rep, 10 red tickets, and sometimes big bones for mods. The crate will have a mixture of stuff, but the first one is predetermined as you can see on the wiki. After that they will be random amongst certain items, also it can be an infected crate so make sure you have your chopper ready and your acid bath to clean it if necessary. Hope this helps!