Embarrassingly, I have five Marriott/SPG cards. For various reasons, I'm stuck with them all for for 6+ months.
Which one should I use for stays?
Don't know why you think that's embarrassing, but use anyone one that gets 6x that meets your needs.
If you have the Luxury Card by Amex perhaps that would be a good option for booking one of your more expensive stays since you get 6x points and a statement credit. The MRPP is good for basic Marriott purchases because of its 6x power, as well.
And yeah, that's not embarrassing. In some circles people would say, "Only 5?" haha.
If you're LTPP, use a 6x points one.
If you have the old Chase Marriott Rewards card that gives you an elite night for every $3000 spend, and if nights matter more than points to you in achieving your lifetime status, use that one.
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