I typically use Crisp because I like it and it's easy to source here. I've used Thomas-Fawcett and Warminster Floor malted too. I really liked Thomas-Fawcett but wasn't to find it around here anymore. The bag of Warminster I used didn't have any major positive or negatives over Crisp so price and availability won out for me.
My general feeling at this point is MO is good, use what you can get.
Paul