The background just started to blur at around 1/100 shutter speed but a real sense of movement became apparent at around 1/50 which was where the most pleasing effects occurred. I managed to keep the subject relatively clear up to around 1/10 but after this it was difficult to pan with enough accuracy. The effects after this were not unpleasant however, and I really like the sense of action a long shutter speed can convey. After 1/3 though, the images became unusable.
My two favourite images from exercises 4 and 5 are below:
Under normal circumstances, the movement in this image may be too much. However, with the busy background I think the exaggerated movement conveys a sense of drama the other images don't have.
This image shows just the right balance between background blur and subject sharpness. It is my favourite image of both exercises. I do like the effect in the latter images of this exercise, even if the subject is not sharp because it gives a surreal effect taking you away from the rather mundane scene.