I've been using the Logo! series for some time. I first designed a tri-foam controller with it, and I've found all sorts of other uses. I use one in each bay to end the
credit card transaction when the switch is turned to "STOP" because customers would often forget to press the stop button, and I utilized the extra outputs to delay the high-pressure outputs and to blow down the bay hose which speeds up the low-pressure to the gun for the next customer.
The Logo! is not a PLC but a programmable, multi-function relay. It doesn't have any "logic," so it can't do things like create an accumulating timer or bonus-time feature without an incredibly complicated ladder program. I tried creating a simple accumulating timer program, and just building it to allow 12-
coin accumulation it exceeded the memory of the basic Logo!.
You can get a startup kit from Siemens which includes one Logo!, software and cable for about the price of just the one Logo! and cable.