I have been PLT at Marriott for like 3 years. This year, (as it ends not a moment too soon..) I stayed approx. 130 nights w/ Marriott.

I also stayed 82 nights @ Hilton, and qualified for Diamond there. I have been far more impressed (for the most part) with Hilton. First, they actually dedicate a separate phone # to Diamond ONLY. Most of the people there are very nice and efficient. At Marriott, PLT shares same phone # with basically rest of the world.
Second, for the most part. Hilton points are much easier (than Marriott PLT)to redeem once Diamond.
Third, Hilton gives AAdvantage miles and HHonors points for each stay (Double Dip).
Fourth, (and not a minor point) lounges are open on the weekend.
Fifth, I agree with all who have said that Marriott Customer Service has declined recently.
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