Cybersource vs Authorize.net vs ???

I'm doing some research on payment gateways trying to come up with options that are developer friendly. My client has looked into a merchant account with B of A which would use Cybersource. However their programming interface seem awkward, and to use the more advanced interface with .NET requires loading libraries on the server, which isn't really an option in many hosted environments. Authorize.net seems to have a well supported interface. I'm just wondering if anyone has any opinions on these or any other gateway options. Also, if anyone has experience with Cybersource, is my take on it accurate?