I use StartSSL and use their SAN and wildcard support One thing to point out, the cost is for validation rather than individual certificates, so you can issue multiple within the year as you like (assuming you can validate the domain).
However like another has posted I had a particular domain rejected as being too similar to other sites (despite owning the domain for longer), I agree this is quite ridiculous but for me the cost implication of moving to another supplier was rather huge. Otherwise their support is very good and you can reissue certs as long as the main CN is different. Hence I've started using a subdomain like
c0.ssl.domain.com as the CN and added the rest as SAN entries so that I could reissue as much as needed.
~Mat