We use enom, and used bulkregister prior. Both are good, we stuck with enom because it is a tad bit cheaper...

Support is same for both we found :)

I am scared of cheap servers, a friend of mine tried one at united colo and their bandwidth was terrible, even with a light load on their server. For quality dedicated server we strongly recomend DV2/transactglobal. If you want reseller programs, consider reading reviews at webhostingtalk or comparewebresellers.com.