I have been giving equal amounts of business to Hilton and Marirott the past few years.
With Hilton's recent devaluation, I am moving most of my business to Marriott. Especially now that I am at about 900 lifetime nights and see lifetime Platinum approaching (versus about 850 with Hiltons that will count towards nought).
No question that Marriotts have much greater consistency. And are much stronger on the high end, especially with JW and RC. Big pluses.
The big minus for Marriott is HGI versus Courtyard. HGIs have it just right. Courtyards seem stale--and suffer from the "no free breakfast for elites" rule.