This is a fine hotel, but Istanbul has (to my mind) the biggest contrast between Hyatt hotels in Europe. The Park Hamburg and Grand Berlin are essentially within a whisker of each other (hard and soft product) and while it's been a while since I was in Dubai I recall that the Park and Grand there have very different hard product but not dissimilar soft. Actually I guess that Paris also has a big difference (PHV and CdG) but I was in the CdG two weeks ago and service/soft was actually pretty good.
The Park and Grand here in IST aren't a million miles apart in terms of hard product (and this not saying that the Park isn't nice, but it's not wow! and the Grand is pretty good) but the staff/service/soft product are immeasurably better at the Park than here at the Grand. For instance, I got an (unasked for) upgrade to a suite, but with twin beds rather than the king I booked. I went to the Club desk to ask for a king club room which was sorted, but no apology for giving me a twin in the first place. That key didn't work the lift, so back again to get it recoded and again no apology for the problem. To compare, the PH sent a member of staff out at 1am to look for me when I couldn't find them walking home a bit pissed.
There was a thread somewhere about PHs that 'get it' and I'd firmly say that on the basis of my recent visits IST is up there, while the GH is playing somewhere about the same level as Birmingham and CDG... fine, but nothing more.
[caveat - this is all from the perspective of someone who stays exclusively at European Hyatts, so clearly it's still a great hotel and miles better than most of the US Hyatts, but the bar here is veeeeerry high
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