Actually, I should be clear, I don't recall ever being straight up lied to from someone with a replica bike. I want to make sure I speak correctly.
I simply think that a replica, should be an actual replica, a faithful reproduction of the original. I take the biggest issue with the replica bikes that also have all these "upgrades". If someone is racing, let's say a replica Manx, then it should have a magneto, an Amal GP carb and a gearbox that matches original spec. etc.
To me, things are misleading with electronic ignitions, concentric or Mikuni carbs and 6 speed TTI gearboxes. I don't think that a replica, with those "upgrades" is actually replicating an original. Those things start to fall into the world of speculative fantasy that some like to consider "development".
I also think the a replica Manx should have 19" wheels.
A real replica Manx would be more than just a cosmetic representation of the original.
For obvious reasons of track and rider safety, I absolutely make room for belt drive primaries, modern tires and even enclosed valve springs. While those aren't original spec, I feel that rider safety, certainly outweighs originality.