I used to do it all the time. Especially when I lived in Treasure Beach but..... Treasure Beach is not so much a destination as it is a lifestyle and a little more laid back than Negril. I think you get hustled an harassed a lot less and generally speaking there is not as many transplants from other areas of Jamaica there as in Negril so it is more "family".
A day trip is okay but staying a few days or a week or more will allow you to experience Jamaica a little more like a local than a tourist.
Just my opinion.
Peace and Guidance