My slight take on this is that I've had my Steinhart Ocean GMT (ETA movement) now for a few months, and I'm amazed by its accuracy! Its basically gains around 1sec a day, which is deeply impressive. Most of my collection have been quartz, and I was rather wary of buying an auto, as my Seiko SKX007, my only other auto, gains around 1 minute a day! It is old and I bought it secondhand - even though I had it serviced after I bought it, its never been very accurate.
So, I think the Steinhart is great, at a fraction of the price of other flash brands with similar movements - and half the cost of the almost identical Christopher Ward product, that has the exact same ETA movement! And the Steinhart is water resistant to 300m rather than 200m, which is of course crucially important!