Oooh interesting discussion.
We changed from using solenoid valves in IA3 to ball valves in IA5 because we always seemed to have problems venting the ram properly. We have certainly solved that in IA5 but whether that is purely down to the ball valves or whether the additional buffer tanks help, Im not sure.
Our ram is 80 bore * 170 stroke and the buffer tanks are more than 5 times that volume. We can get around 25-30 flips out of a single bottle of gas.

Rob