I have a "II" and initially tried to end my long exposures using the film advance lever, with disastrous result. YMMV but the couple negs I had that I used this with were definitely ruined by the drag. Normal range of tones as well, not like the streetlights at night example posted above. The shutter speed change method works well though, it really is a nice camera.
Some of my cameras and remote controls have a Bulb (B) exposure feature; some have a Timed (T) exposure feature. I use them both and I like them both. I use a piece of thick black felt material to cover my lens while I am manually closing the shutter at the end of a timed (T) exposure. I also use the felt to cover my lens while performing a long T or B exposure at night when a vehicle just happens to drive by with its headlights on.
So, in answer to your question, no, I do not have an issue with it. I do, however, have an issue if the camera is incorrectly calling a T exposure a B exposure. Exactly how is it labeled on your camera?
The fujis are marked "T". It is a bit annoying, but in their defense the camera really ideal for hand held exposures. Not a great defense I know, but there are workarounds.