I too was surprised at how low the exposures were. I was getting about 3 secs with my Durst M605. I substituted my 100W bulb for a 75W. Even then the exposures were still very modest. Dialling in C does help if there is no other way.
Fortunately there is less need to dodge and burn with RA4 or at least I found this to be so. The exposures I had make D&B nearly impossible.