I've stayed at all three listed above and The San Luis Resort is by far the nicest. Also have the best steakhouse in Galveston on the premisis.
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"Things turn out best for those who make the best of the way things turn out" - Zachary Troy Schrah - a young man with vision far beyond his years.
All 3 of those are nice. It really depends what you are looking for. If you're just going fishing and really only need a place to shower and sleep then I like the Harbor House on Harborside Dr. Its less expensive and the rooms are better than those at other 75-95 dollar places. If its a trip where you need amenities then the three listed are good choices. I've stayed at all 3 and been happy. If I have time to plan and am going to be there for a week or so then I'll usually look at house rentals.