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Thanking you kindly. HSS works a treat for setups like this.

I need to get a flash and trigger that supports HSS, atm i have to mess around with NDs to stop down and it just adds more things into the mix

ND's can still get the same result but can be a bit messy alright. Depending on how much ambient light you have they can make it a pain to focus too. HSS is the way to go for sure.