Charlie,
I use a Uwatec Air-X.  It will handle O2 limits to 50%.  It is also
downloadable to a PC via an interface unit (called a MemoMouse).  Yup,
the MemoMouse costs extra.  But, the MemoMouse also stores up to 66
hours of bottom time, so if you are on vacation and don't want to lug a
laptop around with you, its a good way to store your data for later on.
 Of course if you want to view your profile immediately....well, guess
you gotta have the laptop with you.

There are some downsides to the Uwatecs.  When it is time to replace the
battery, you have to return the unit to the factory.  However, the
upside of that is, they do a complete overhaul and calibration on it and
you essentially get a new computer in return.  The battery on mine
generally lasts about 5 years.  The newer models (Air-Z) have a
backlight feature.  This is good for nightdives, but you get
significantly less battery life.  The Air-X and Air-Z both are hoseless
computers and utilize a small transmitter on the HP port.

I also have a Pro-Nitrox computer which is almost the same as the Air-X
except it cannot monitor tank pressure.

I bought my Air-X used on Ebay a couple of years ago, and the battery is
still going strong.  Shop around.  Look on Ebay and you can get an idea
of whats available, how much it costs, and general features, and then
make a decision.

There are lots of good dive computers out there.  I have only use the
Uwatecs and have been satisfied thus far.  I have read of some folks
that don't like the Uwatecs.  But make your own decision.

A couple of years ago, I was on a diveboat and overheard one of the
divers complaining that her Oceanic computer was flooded and that was
the 2nd or 3rd one that had flooded.

Andy

Suunto Vyper

Vyper or Vytec if youve got more money, want gas switching and AI.

Build the interface for around $5usd

Charlie,

I have an Aeris Atmos 2. It is my third Aeris dive computer and by far
the best. It is very user friendly, easy to program, and has a good,
easy to read display, which to me is very important. The Atmos 2 has
nitrox as well as gauge modes, and the optional dive downloader
package is also pretty decent. In my experience, Aeris has excellent
customer service.

Good luck.

-bob

i fell for the uwatec smart com ... excellent readability, o2 from 21%
to 100%, 99 dive or 50 hour log (100 hr for the smart pro), easy dl of
dives to a pc, good dive log software ...

even after the global recall i still stick with this comp ... my lds
changed the comp for me, took me just 5 minutes to fill in the forms ...

if u dont want ai, the smart pro will do just fine ...

download via infrared (built in the comp) ... any ir interface will do,
tho there are ppl that have trouble with certain interface/pc (or mac)
combinations

2 eurocents

markII