I wouldn't necessarily say "piece of cake" but definitely not a "piece of mushrooms"
FYI, mushrooms are disgusting and taste very nasty.
It is rather easy though if you follow some good documentation. And as long as you realize there may some diversions from a typically install, such as setting up Syslinux instead of Grub or Lilo (or maybe in addition to if you use a universal boot loader).
One other thing, diskless == no swap "drive". I run some truly diskless systems at home (running MythTV over network boot) and I had some major problems at first that ended up being due to low RAM. I upped to the MAX the systems could handle (Epia systems with 1GB) and the problems seem to have pretty much gone away. I stripped down my kernel too, this helped to ensure as little RAM as possible was being used so that when something RAM intensive needed it, it would be there.