Agree with the Hayward Aqua Rite - I've had mine for a year and a half and have only had to clean the cell once (easy), and I had to replace the current limiter (common problem). If you've got a chlorine feeder in your system, the cell will probably fit at that location (mine did, and did for another install on a friends). Then its just installing the flow switch in the system, and tying the power in to your pump timer or pump switch. Of course, it's a little more technical than that - and I think pool companies charge around $300 for the low side and $500 on the higher side for the install. As jblizzle said above, if you've done any work with PVC, it's a simple install. Running the electrical conduit to the box from my timer was the worst part of the install for me (had to reem out the metal hole in the generator box to make a 3/4" conduit fitting work). Well that, and the 400 lbs of salt I had to carry from my car to the backyard lol. But in the end, never having to buy chlorine tabs again, and simply turning the output knob to adjust how much chlorine goes in the pool - that's so worth it. I've only had to add a few bags of salt too since I put it in during March of last year. I think during the summer, I was spending about $100 a month on chlorine tabs and shock. With the deep south summers extending from March and going to October, I was easily able to recoup the costs within a year..as I probably spent $800-$1000 on chlorine the first year I had the pool.