Yeah, Flopside's was pretty cruel, because it was technically 200 floors. Some of the enemies were just downright annoying, too. >_>
Rogueport's was still pretty tough the first time around, tho. I was NOT expecting Bonetail after 99 floors of battles (the last 20 of which were just pure hell). Kinda bummed me out when I found out that you could only battle Bonetail the one time, tho. I was so ready for him the second time around.