Visited here labor day weeekend ... It was fun, though the traffic was horrible. Ofcourse it was labor day weekend but I would suggest checking the traffic if you are travelling on a weekend..... esp coz the highway ( route 27 ..don't know if i can call it highway , travel speed of 30 /hr) runs through the hampton towns and can make your trip longer. Parking is $ 8 and then we strolled around the lighthouse, hiking and just watching waves. Its a quiet beach , good for just unwinding and relaxing. You can bring a picnic basket and just enjoy the quietness. There is also a small bar where you can get something for a quick bite . I visited here labor day and it wasn't crowded so i guess other days will even be quieter. Going into the lighthouse itself is $ 9 which i though was bit expensive. If you are interested in history and want to have a 360 view then may be its worth but for me it was pricey.
If you are staying around in long island then a trip is worth it. I didn't think it was worth staying overnight though .