Good luck. From what I have seen they are very expensive and for non-residential systems. Most systems, my Hayward Pro Logic included, work off of % of cells capable output. This very much frustrated me due to needing to balance that setting and the fact it is on all times when pump is running.... I got used to it. Once you find right settings after a few weeks of trial and error, all is good. My settings for a 19k vinyl IGP are - 1HP pump at low for 12 hours per day and IC-15 cell/Prologic setting at 15%. This keeps me around 7ppm, which is where I like it.
There are ORP based systems that adjust output based on the ORP of the water but they have a problem with high CYA levels seen in outdoor pools and therefore aren't reliable. There have been several reports of people abandoning the ORP section and just using the swcg on a timed basis.
It has temperature compensation, but in reality all I think that does is boost/buck to get the equivalent of your "dialed in" setting as the water gets colder or warmer.
Just set mine up, am interested to see how well it works. Cold water wont be much of an issue in my pool, but we get full sun for at least 12 hours/day on it so the compensation might help as the water heats up.
None of the systems that automate the delivery of chlorine based on actual levels in the pool are really reliable enough for residential use. For an outdoor residential pool they add very little value, as chlorine demand is fairly predictable and FC levels are reasonably stable. A simple percentage based control will give you almost at good results and will be much more reliable and less expensive.