I've had a standing order at Phantom Zone Parramatta since G1 days - it's good for new comics that I pre-order. I've pre-ordered the TPBs for the IDW Time Wars reprint and Transformers Animated comics... never pre-ordered a TPB before so I'll see how I go with that. In terms of pre-ordered individual issues they've always been good except for that one brief moment during the Dreamwave era when there was a problem with distribution, but that was an issue with Diamond not PZ. Thankfully it was sorted out.