after nearly burning out on the last ~42 hour job, at the current company i tried 30 hours and i love it. they do want to convince me to go full time, but for now i refused (stating that i don't think i'd be as productive and just cost the company more money without delivering another 33% of work). a lot of my colleagues and even friends at other companies downgraded to 30 hours (or never upgraded after finishing university).

i earn enough to get by but don't save as much as others at my age (for reference, i'm 35). i work 6 hours a day, 5 days a week (others work 7.5 hours a day and just take friday off). i don't get paid overtime but be do have comp time.

the upsides, in my opinion:

* i'm better rested, more concentrated and productive so the company gets more bang for the buck

* i spend a lot of my free time in the gym (this hopefully means i'm reasonably healthy which would be a plus for the company due to less sick time off)

* the rest of my free time i spend programming interesting private non-commercial projects; i.e. free education and experience that benefits my employer (sometimes it also leads to open source libraries we can use at work)

* the other rest of my free time i spend reading about IT (things like HN), which, again, +experience

* when schedules get tight i tend to accumulate overtime, as soon as that passes i tend to take time off. this means the company doesn't have to pay me for twiddling my thumbs and waiting for the clock

in my opinion it's mostly a win-win situation for both me and my employer.