> Anyone buying ECC RAM for servers is buying on the same market as you building a new desktop computer.

Even when the sticks are completely incompatible with each other? I think servers tend to use RDIMM, desktops use UDIMM. Personally I'm not seeing as step increase in (b2b) RDIMMs compared to the same stores selling UDIMM (b2c), but I'm also looking at different stores tailored towards different types of users.