Synergy Wholesale Pty Ltd

I have about 200 domains registered and about 40 hosted through Synergy. In terms of wholesaling, their product is flexible and customisable, though a little limited in scope. Their pricing is great and their automated provisioning is fantastic. Support is good -- not always blindingly fast but helpful and knowledgeable, and you get actual technicians, not people running through a script. I've only had one major issue, involving a bad spam filter update a couple of years ago, which caused most outgoing emails to be blocked as spam for a day or so (fortunately at that point I had very few services hosted with them). Ever since then, things have been great.