Was comparing some specs on trenchers. Happens to be an attachment for a skid steer, but may end up with a ex rental company 'standard trencher' around 40 hp. For a 4 foot trench depth the Bobcat, CAT, and John Deere all have different chain pitches but the same chain speed. How important are these chain pitch sizes? Does pitch affect chain width? strength? stability? Why the different pitches by manufacturer? Looking at various catalogues, etc, there are lots of commentary explaining the variants in the pitch dimension and how to measure as well as cautions about mixing parts, etc etc, but not necessarily any particular issues with the chain pitch, per se.
Chain pitch is just the length of the links. The smaller the pitch the more links there are in a given length of chain. Basically the only reason each manufacturer uses a different pitch is so that parts can not be interchanged and for what ever reason their engineers decided that pitch was best. The only thing that a lower pitch chain will have is more pieces to wear and with the pins closer together you may see a little bit more side to side flex when the chain has some hours on it but if there is it wont be enough to notice. The brands you listed are all good brands and i would go with which ever has the best dealer or parts sources for because they will all wear and eventually need work done to them