We're not snowbirds or fulltimers but we have always enjoyed the RGV. For one, I work in that area on occasion and use the rv parks. It's very close to home for us which is less than three hours.
That said, a lot of the parks are outdated and worn out. The events are pretty much standard; shuffle board, country western dancing, mah jong(?), potlucks, and holiday dinners. Nothing too exciting. We like to get out and go to the state parks, birding, riding bikes, exercise, visiting new places, etc. I don't care much for just sitting around.
And being under 60 we find that we are shunned a bit because we are younger to the point that people ask us why we are at the park or using the facilities, "Are you supposed to be here?" and we get that a lot.
We still like it though and everything is cyclical. We will be doing the same someday too I imagine :)