The choice of developer, as many people said, depends mainly on the artistic idea one wants to obtain, if not constrained by economical or other practical reasons. I particularly like black and white images with a classic, warm look and that is the main reason why I settled on Tri-x in D76 1+1 and Agfa APX-100 in Rodinal 1+50. They just make so perfect combinations for me, I cannot, at the moment, think of changing any of them. Moreover I donīt have yet many years of experience and keeping the same settings may be good for consistency as well.