Rob, assuming your HP ram is 50mm bore, I would stick to your 100mm bore LP gear, you have the potential to get a greater performance.

Ultimately HP will win on outright power but that does not guarantee a winning machine. You need to decide on what performance you require and that in turn will influence whether you go LP / HP. If you are happy with lots of 1m high flips then LP is fine, if you want 3m high flips then LP is struggling and you are best going HP.