Any luck with buying used heads online?

[shootshescores]

I've been struggling to save for new heads for a long time now. I find myself getting nowhere fast with it. When an opportunity comes up there's always a setback following close behind. I have recently been cruising ebay and some online classifieds checking out some Trick Flow Twisted Wedge Aluminum Heads.

Has anyone had any luck buying used heads online? What are some things to be aware of and look out for?

 

[vikingpower]

Even if you buy some online, you'll probably end up spending some cash getting them rebuilt- such as valve guides and a fresh set of springs.
As we all know, a good set of heads is not something hard to sell... which begs the question, why cant they sell them locally?