You may have gotten more responses if this was in the Gear secton, not the Ski Review section. Maybe a mod can move it. You should include some info about how big you are, where you ski and how well or fast you prefer to ski. These factors contribute to how long your ski should be.
The Rev 85 will have many more reviews and discussions, if you use the search function, you will find all the info you need.. It is a very capable, traditional Head carving ski that holds well on harder snow. I owned the Rev 85 and sold it because I prefer a more narrow ski, but, that is a personal preference. Never skied the Rev 80, but, Head has been making fine carving skis in that width range for many years, all have solid reviews. If you can get a great deal on a 80, I say do it. I would prefer the narrower ski if you live in the east and ski harder snow, the 85 might serve better in softer snow. Not much difference between Rev skis with only 5 mm change at mid-ski.
I would disregard the differences between a Head PRD 11 and PRD 12. Both are great bindings for a typical recreational skier where the DIN setting is between 5 and 8.