Dont get me wrong, I do love large reef aquariums. I did leave a few times for similar reasons as Brad & Jon.
My current downsizing issues are more to do with the previously mentioned cost reasons and also the fact that I live in the country. My large tanks, with all its plumbing and devices and a jammillion plugs ins, scares of any chance of one of the locals looking after it while I,m away.
Most of the ones I read about on other boards are usually younger and have major changes going on in their lives.