We don't really care for the area, but some folks really like it. I would not book more than a couple of nights until you are sure that you will like the park. There are 100's of parks down there, so the key is to find one with friendly people in it and also in a decent area. It tends to be very very windy and it is also very dusty. Makes it hard to open windows for fresh air. Also, English is a second language down there. I'll take FL over the RGV any day.
We first tried the highly rated Llano Grande in Mercedes and found the people less than friendly. We then moved to Mission West in Mission and spent two months there. We met some new friends there that we have kept in touch with since then (07' / 08' winter). We just passed through and spent the month of November to visit. I for one was happy to be leaving. Back in FL where they speak English on TV and radio.
2006 Fleetwood Bounder 35E