Accor v/s Marriot

So Accor(Axis Atlas) and Marriot(Amex Platinum Travel) it is. Based on your experiences and research, which one fo you think has better coverage in terms of properties in tourist spots, location, and value for money? Both hotel chains have some amazing hotels under them and seem to be one of the finest.

Also, for the ones who have redeemed their points using the above CCs, what has been your return rate and how much have you had to spend? May not be exactly specific, but ballpark figures would also do.