Would there be an Invicta submarine r if there was not a Rolex of similar shape? In other words if you buy one you are hankering for the other.
If you like the style but can't afford a Rolex Submariner than the Invicta will give you the style for a fraction of the price.
If you want a gold looking watch the Invicta is gold plated whereas an all gold Rolex Submariner is solid 18K and costs £22000.
Even a stainless Rolex sub is now around £6000.