Is there any big difference between the three of these? I've taken the ZMassPM and the ZMA Fuel and been happy with them, but I picked up a bottle of the EAS ZMA HP today to give it a try and I noticed that they recommend taking it 1/2 hour before working out and 1/2 hour before bed instead of just the 1/2 hour before bed that the ZMassPM and ZMA Fuel had recommended.