I am happily using Dynamic DNS. I use DirectUpdate to perform my updates. (http://www.directupdate.net). I have been using this application for a long time. Works under Windows XX as a service. I assume you have your domains setup for DDNS within the control panel.
All dynamic DNS systems should be working and backwards compatible with the old system. We recommend using an auth token in place of your regular account password, but both will still work.