Do you seek out fixed-size (approximate) moves or is it an opportunity-by-opportunity decision where you'd accept a potential 50 pip move as well as a 300 pip move?
A little of both. I rarely go for the 50 pip move. Most of the time I have about 6 pairs looking for 150+ pip moves. But frequently the setup degenerates, and I end up taking the 50 pips if I can get them.