In that scenario yes, the machine with the greater reach would have a better chance. However, NST is the only invertible horizontal bar spinner in the UK. Massacre is to high up and is non-invertible so it doesn't fit into the same category. The new machine is very unlikely to be in that position since NST is probably going to retire this year when Shard, Sams new vertical spinner, takes over.

The main reason I say it need to be any bigger is because you then start using weight to get adequate support for the weapon, this reduces the weight you have for armour an a system that is powerful and robust enough to take the larger diameter weapon. NST's is around 600mm so a 700mm weapon would be good.