IWC has a much more tightly-controlled distribution than Omega, making IWC's slightly more exclusive. Just call around to jewelry and watch shops and see how many are authorized Omega dealers vs. IWC dealers--the ratio is probably somewhere around a low of 7:1, to possibly 10:1.
In the luxury watch pyramid (with Patek Philippe at the top), I'd personally rank IWC very near the top (with the likes of JLC, Audemars Piguet, Franck Muller, etc.). I would put Omega in the mid-to-upper range (with Breitling, Ebel, Raymond Weil, Cartier, Chopard, Corum, etc.). IMO, Rolex would straddle the area between the two. Of course, each manufacture has a range of models up and down the spectrum, so ranking them is an imprecise science--averaging out the entire line.
This is my personal opinion, having handled and inspected a great many of many of these watch models, knowing their lines, and having spoken to many of the manufacturer's representatives. I'm positive there will be those who disagree with me, and that's fine.
Before buying an IWC, one should be aware that IWC's are serviced only by IWC in New York. You will not find parts or anyone else to service them, because IWC does not distribute those parts to anyone. A full overhaul should be performed about every 5 years, and will run about $500 for a mid-range IWC model (MSRP $3000-6000).
The IWC Aquatimer is one awesome watch. It is in use by a number of German combat-swimmer types, and is not just a showy luxury diver's watch. I do not personally own one, but a close cousin just acquired one as a wedding gift from his bride, and it was a beauty.
Bottom line, you will not be disappointed in either an IWC Aquatimer or Omega SMP. But, the reality is that there are simply many more (probably tens of thousands) of SMP's produced each year, while Aquatimer production is probably a fraction of that.
HTH
