It doesn't make sense to base your production system on a hack of your provider's platform. 64bit OS was the reason I ditched Slicehost too, although I knew about this hack.
A hack? To the best of my knowledge, both providers allow users to install arbitrary Linux distributions. It's not against any rules, so I wouldn't consider this a hack.
Go through all that when Linode (or others) lets me click a button to get the same thing? No thanks - it looks like a 'hack' to me. Sure, I don't mind running my own system, but imagine doing that every time I decide to provision a new one - yuck!