I had a Lock Right locker in my '78 1/2 ton. It was cheap to buy, but loud when driving around in town. I also had an aluminum topper on it that seemed to amplify the noise from the differential. It did work great for about a year and a half then it broke when I was crossing part of the road that washed out.
They aren't as strong as other types of lockers on the market. They aren't typically recommended for tires larger than 33". That being said someone will say they have run them with 44" Bogger Swampers and have had no issues.
It can make driving in winter interesting also. With both tires locked up the rear end will like to fishtail around. Very fun if you are out playing and want to do power slides around all corners. But oncoming traffic doesn't like to see that when you are climbing up a steep hill around a corner and the rear end steps out.