How experienced of a diver were you when you started to use one? I have 7 dives under my belt... including my discover scuba and OW cert dives and have never seen a computer at work. Would I feel comfortable strapping one on my wrist and relying only on that with 5 minutes of training in it's use? No. Maybe I'm overly conservative. I don't mind that. However, I'd probably feel more comfortable with doing something like that had I had some very basic PDC training in my OW class. At least I'd know basically how to read it and what things were. Even with a PDC, I'd probably plan my dives using tables...at least in the beginning.
I did my first 120 dives or so using tables. Those dives were the best of my life: Singapore, Malaysia, Thailand, the Maldives. Of course I like tables. Specifically, the NAUI tables.
But Nitrox complicates life. Not only do I need to fiddle with the computer to make sure it has the right mix and then watch the NDL, I have a new thing with total oxygen (OTL - Oxygen Toxicity Limit, as it's known). One more thing to mess with and another table to use if I'm not using a computer. Now your NDL is the shorter of nitrogen uptake or oxygen exposure limit. Both, of course, are a function of depth and time. That's just too much stuff to write on a slate and track underwater. So, I bought a computer. Four of them for our small herd.
When you go to buy your computer, have them demonstrate ALL of the functions. Pay careful attention to the menu navigation. Pay even more attention to what you might want to do while submerged. Three button computers are easier to use than 2 button computers which are (perhaps) easier than 1 button computers. I had a long discussion with a fellow one day and we came to the conclusion that the more buttons the easier. But they need to be big buttons and well spaced for cold water mittens. Look at the owner's manual. If it is written in Klingon, try another computer.
I don't believe a 5 minute introduction is sufficient for a computer that tracks altitude, fresh/salt, ppO2, a couple of mixes, nitrogen bar graph, oxygen bar graph, alarm indications, ascent rate indication, Nitrox mix default at midnight, etc. There's just more to it than that. Like log book functions, PC interface functions, downloading, battery replacement, etc.
One problem with
some computers is that the only time you can see an alarm icon is a) in the book, b) on the startup screen where it is surrounded by jibberish and c) when it applies to you and you are underwater. AFAIK, very few computers let you simulate a dive and see what the display will look like when it really matters. The first time you get that mandatory deco indication may be the very first time you have ever seen it. "Hm... I wonder what that means?" I don't think any of the manuals can be used under water.
One computer that does allow for dive simulation is the Liquivision X1 with the V-Planner Live software. It's terribly expensive. I WANT one...
Sadly, I don't think you will find more experienced divers that are still using tables. I understand your desire to dive with more experienced people. I felt the same way. That's why I took NAUI OW I, OW II, Advanced OW and Rescue as back-to-back courses. I spent a lot of time with the instructor before I ventured forth to conquer the oceans.
Here's an Oceanic computer for $200
Oceanic Veo 180 Wrist Computer Another for $150
Oceanic Veo 100 Wrist Computer (My grandson has this one in a console).
Here's one that costs a bit more but the downloader is CHEAP!
Uwatec Aladin Prime Wrist Dive Computer I bought this for my wife but she took my NiTek Duo so now I'm using it. It takes an hour or so to catch on to the menu navigation. The book doesn't help. As to downloading: you need an IR dongle for your PC like this:
DealExtreme: $4.83 USB IRDA Dongle The software is EXCELLENT and it comes free with the computer.
Don't overlook the cost of the downloader gadget. For the NiTek Duo it is a couple of hundred dollars depending on where you buy it. I got a couple of these computers at a great price from ScubaToys but the last time I looked, the price was back up where everybody else is. I think I paid $50 for the downloader as an incremental cost for the computer.
If you really want, and you probably won't, you can put most computers in GAUGE mode and dive tables. As a refresher, perhaps?
Richard