My company has had 9/80s for as long as I've worked there (~8 years) and I'm a fan. Its great having a 3-day weekend every other week and nice to have a weekday off to get done all the stuff that you can only do 9-5 on weekdays. I would end up working 9+ hours a day even if they were 8 hour work days, so the 9/80 is all positive for me. I've never been pressured to work on my off Friday.