I bought the MM 502 kit along with a keyboard, a couple spare keychain transmitters, two batteries, a solar panel, and the electric locking unit. I didn't want to run power out to that area so used their solar panel and install two batteries in the control box as recommended. I live in the High Desert and so far haven't had any problems with running out of juice. We use the gates (twin 14' chain link) several times a day during the week and a bit more on the weekends. The electric lock works great and will prevent someone from forcing the gates open or removing an actuator to gain access. The locking pins they sell for the actuator are really to prevent someone from stealing the actuator, not gaining access since the actuators should be on the inside of the closed gate anyway. The keypad is kind of lame and I only trust mine inside the yard and use it to open my gates (mounted on carport) while working around the house without needing to go to one of the vehicles and using a transmitter. They (keypad) are just too easy to open which would reveal the dip switch settings, allowing somebody to program their own transmitter and gain access. I also keep a transmitter on one of those rubber wrist loop things hung up in the house. This allows us to open the gate for company and I can slip it over my wrist while tractoring around the property. Anywho, mine has worked great for over two years.