No-ip ( http://www.noip.com/ ) still offer a free service. I use them and I've found them entirely satisfactory.
I use dnsexit.com, and not had any problems. However, I had to use a custom updater on my Draytek, and could see no way to update on my Billion NL.
No, I think you have to do that manually. I used their free service for a couple of months, but I've since upgraded to the paid-for service.