3 months in and I haven't had many problems. Granted, I didn't really do any stays in August or September, but I've done a lot in October and November. Mostly legacy Marriott properties (Marriott, Courtyard, Autograph), but a couple Sheratons as well. For the most part, it's been pretty consistent - no problems with lounge access, often get an upgraded room (mostly better views, but a suite or larger sized room here and there too). With 1 exception, stays have posted within a couple days (which was the old norm), and from what I can tell, welcome points + megabonus + week lounge points have posted correctly. With the F&B platinum amenity at Courtyards (and the other limited service brands), I'm now considering them, instead of as last resorts as I did pre-8/18, and have been happy with my experience thus far.

There was one case of the $10 F&B credit not being properly deducted, but I assume that's a Courtyard property-specific issue with those being new; and one stay didn't post for 2+ weeks (until I submitted the missing stay form and it "magically" showed up before the representative responded). But overall, I've been satisfied with the experience, and am excited for some more options that the SPG properties provide.