... I was about to order the cressi giotto (I liked the price, easy to read, does what all the other computers do), until someone from a dive shop talked me out of that one and convinced me to go with just the Suunto d4i novo. I know it's pricier but certain colors are on sale right now. The giotto might be too big, I think? I have a small wrist, and the suunto, maybemire difficult to read since it's smaller
I think big is a plus: it's easier to see the numbers. The strap is too long for slim bare wrist (it's long enough for thick wrist in drysuit and gloves, so...), and it's not the usual watch band fitting -- at least not on my leonardo and I believe giotto is the same. So it's not easy to replace with e.g. one of these: CountyComm - NITROX-17 A 17" Watch Band For Divers
Note that d4i has air integration, too. If you don't want that, oceanic geo 2 is a popular choice in the watch size. If you want that in puck or bigger size, hollis dg02 is about the best bang for the buck you can get, after that you're looking at $1000 price range.
To answer your original question: I go on Caribbean vacations and spend 7-9 days diving in bright sunlight (well, at night too) breathing air from al80 & rental regs. My cressi leonardo turns on when I hit the water and shows me everything I need. It's about zero maintenance: I did replace the battery once. Sometimes I even forget to change the clock to local time.