My kids went from Block to regular and vastly prefer it. There isn't that much homework when you are doing just one 45 minute lesson per day. You are only typically learning one small thing - rather than a whole 85 minute block - so there is less confusion about the math topic. For example, they would be learning multiplication and division in one lesson (just an example, folks) but now they are learning just multiplication. It gives their brain time to digest the information and keep the topics separate.
Many studies show 85 minutes is much too long for a person (or child) to concentrate on a lesson without a break.