For reals?
It's not a must, but I read enough on here that convinced me to go with it. Plus talking with Christo and Robbie
There are some threads on here so you can decide yourself
I went ahead and installed both lockers. I like having both ATRAC and lockers. More tools (Tim the tool man ah ah arrrg) provides greater equipment capabilities. Thought the real capability comes from the 8 ball behind the wheel.