Before we can answer that question, we first need to talk about the different types of dive computers.
Air-Integrated: These computers display your tank's air pressure digitally, also proving you with your Remaining Breathing/Bottom Time. This tells you how many minutes of breathing time you have remaining, based on your rate of consumption.
Wrist Computer: These computers are worn like a wrist-watch. Depending on the design, they can be air-integrated or not.
Console Computer: These computers are attached to your regulator via a high pressure hose and can be air-integrated or have a traditional analog pressure gauge.
Digital Compass: Instead of analog compasses, some computers have a digital compass that allow you to set bearings for easier navigation.
Back-Lighting: Most modern computers have some sort of back-lighting to make seeing the screen easier in both bright, shallow water as well as deeper, darker water. Many of the newest dive computers have color screens to make reading the screen even easier.
Transmitter Computers: These computers replace the high pressure hose with a screw-in transmitter. Th transmitter sends a radio signal to the dive computer, providing it with the pressure data from your tank.
Deciding which computer is best for you, like all major scuba equipment, depends on the type of diving you are doing and plan on doing in the future. All dive computers will function as designed and will give you the basic information needed to plan your dives. The difference between computers then lays in what added features they can offer, and which one's you'll actually utilize.
Additionally, the size of the screen and numbers is often very important to divers, especially if they have eye sight issues. While a small, wrist watch style of computer is great for stream-lining your gear, if you can't see the screen, it's essentially useless.
As divers, we are always looking for ways to reduce bulk and make ourselves more hydrodynamic. Using a Transmitter Computer eliminates one of our hoses, and when coupled with a BCD that has an Integrated Alternate Air Source (Air II, Air Source), your regulator goes from having 4 hoses to 2, significantly reducing drag.
Purchasing a Dive Computer is an important decision. Before you buy, come by the shop and let us show you the differences in them and we'll match you with the best computer for your style of diving. And as always, you are invited to try any and all of our equipment in our pool before you buy it!