OK, this is possibly not a mainstream bargain as to take real advantage of it you need to be looking at some of the more expensive watches, but if you're after an Omega, a nice Breitling, a TAG, or anything else at that end of the market, I doubt you'll beat the prices here (especially as authorised dealers of these prestige brands are not normally allowed to discount at all).
eg. An Omega Seamaster 2221.80 can be had for £779 shipped which is the best price online by a LONG way, and the next cheapest at £840 is from an unauthorised dealer, so you'll have all sorts of hassle if it comes to needing servicing or any warranty assistance. I've been looking at getting one of these for several years and in all that time I've never seen one of these available from an authorised dealer for less than £950, so this is a huge saving over that.
Like I say, maybe not for everyone, but you genuinely won't beat these prices for watches at this end of the market, especially from a fully authorised dealer.