from personal experience and countless hours of reading/reviewing member posts and pix, there are many COMBINATION of steelfish...factories often shift various components around to make replicas...if you read the various steelfish posts like Dovo's and BT's, you will see many differences...
in general, most asian models do not have ar...and most swiss fish do have ar...but there are exceptions - as Dovo's post reveals...variation in cases exist - as Cougaree mentions - with asian cases generally not able to accept swiss or gen dials...some cases thicker than others...etc, etc...and yes - some asian fish also have swiss cases...yup - no rhyme or reason; but explainable that factories use whatever they have in stock...
movements on swiss can be 2824-2 nickel plated, 2824-2 gold plated, and 2836-2...it's important to check out dial details and overall features to know what you are getting...i tend to find that the older/earlier release models are the best featured...also, you need to keep in mind that dealers sell "swiss" steelfish with eta stamped movements...some are actually clone movements that are identifiable by various movement components; taking a trained eye to spot...but some are definitely genuine...
last intelligence on the best swiss fish is that they are discontinued and not available from the dealers...and yes - they show them on their sites - but that does not mean they are in stock and/or have the same specs as advertised...
best to learn all you can and buy from a reliable member and/or dealer...
R-