Did this quest yesterday with a linkshell friend. She was a 43 Paladin and I was a 42 Dragoon. I went in there originally to scout out the area to see what would aggro and what wouldn't and then return later with a proper party. But she and I wandered in a little too far and decided to just keep going as everything was pretty much Too Weak or Easy Prey. We were super sneak around a few parts and at times we just ran from floor to floor with no problems.
When we got to the top a 60 RDM offered his help and we downed the NM in about a minute and got our keys. We could have probably taken it solo but we didn't want to risk getting links from the fairly crowded room.
We did the whole thing we no aggro and very little fighting (maybe one or two battles just to make room for us). All in all, if you're 40+ and have a tank or mage, you should be okay. Sneak/Invis would be even easier and there's usually high levels near the NM willing to help.
Good luck and congratulations of Rank 4!
EDIT: Forgot to mention that only I had a map and she was able to find her way to the fourth floor on her own without one. But my suggestion is for someone to have one, just in case and to chart the fastest routes through the floors.
Edited, Tue Jan 11 22:25:29 2005