MH5, I haven't stayed there, but the reviews on other sites seem ok:
Both seems to have minor complaints, but in general the place is nice. Several comments discuss the need for a rehab, some wear and tear showing through, but I don't think you'll be dismayed by your stay unless you are hoping for perfection.
I think it depends on what you're looking for and the reason for your visit. If it's convenience to something in the area and using your points, the hotel is great. We have stayed 3 times in the past 5 years and we recommend the hotel to friends. That being said, if I were traveling with my children and just looking for a Marriott hotel to use my points near beach with great pool, it wouldn't be my first choice. The Marco Island Marriott is far superior. However, this hotel is clean, the rooms are spacious and the pool area is nice with an outside tiki bar area overlooking the bay/waterway. The restaurants on site were all good and there are also other local restaurant choices nearby. Keep in mind the beach is across the street from the hotel, but the hotel will shuttle you over which was helpful. Each time we stayed we had great experience with really helpful staff. The hesitation in giving it as high marks as Marco for instance is it's not directly on beach, not big resort with lots of activities, and rooms are becoming dated. But it definitely is nice hotel property in Clearwater.