Why though?

Think of it in terms of cars. Think of a MR2 done up to immitate a F355. Or any 3 series BMW with a M3 badge on. Or some of the abominations that are on eBay as "Escort Cosworth FULL replica"

People that know, will know when it comes to Watches. And you'll be no better than the guys with the cars above. Far better to either save up and buy a genuine Tag/Rolex/Omega (better if its for an anniversary or something IMO) or spend the £100 or so on a genuine but cheaper watch such as a Pulsar or a Seiko.

2p