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make zero difference
I think I pointed out one somewhat significant difference - your front shifter and rear brake are relatively useless; if you've got one hand busy it's good if you can still use the rear shifter and front brake.
The other major difference it makes is that it can be a (potentially dangerous) pain in the arse if you roll the opposite way to everyone else in your country.
I thought the whole UK USA/Euro brake set up was about which side of the road you drive on.
You’re a novice rider, turning right with your right arm out to indicate braking rear brake with left hand, you cross over the painted white line, the rear tyre momentarily slips, big deal. Now swap the brakes around.
Having said that I have a bike set up euro and I’m not dead, yet.