Firstly, let's underscore just how critical your choice of equipment is. Your personal comfort and your personal safety depend upon it. Without the right equipment you may find there are dives you want to make and aren't properly equipped for, leaving you to make the decision not to dive; or to dive and accept a risk factor that perhaps shouldn't be acceptable. When any diver gets into difficulties, he or she usually involves their buddy or other divers in attempting a rescue or, at the very worst, recovering the body. So, you are assuming that risk not just for yourself, but for others too.
Begin looking at equipment by considering the type of diving you will be doing. Try to think ahead. What activities interest you? If all your diving is going to be in tropical waters, you have the same needs as a temperate water diver. The equipment needs of a fishwatcher are very different to those of a wreck diver. Quality equipment will last many years, so it's important to to try to get gear that can adapt to your long-term needs to maximise the return on your investment.
Next start gathering information. Manufacturers' brochures let you see what's available. The better ones don't just display products, they explain the purpose of the equipment, the activities it is suited to, and the features and benefits their particular brand provides. This helps narrow down the choices. For example, you can reject all the regulators that are not designed for cold water diving, if your future interests include winter diving in cold lakes, rivers and quarries.
Other sources of information include the US Navy, whose regulator testing is considered as the industry benchmark.
Equipment courses can be an excellent way to learn more about how to select equipment, how it actually works, how it all interfaces and how to maintain it. A regrettably small number of equipment manufacturers and distributors provide seminars for the general public and those that do should be highly commended for doing so. Let us hope other companies will follow. Some, like DUI, have gone further, providing lectures on defensive diving and encouraging greater responsibility in using their products.
Talking to company representatives at dive shows can also be very productive. The better reps are factory trained and are familiar not just with their own product range, but with their competitors' ranges too. Canvassing other divers' opinions can be simply either informative or misleading. Often, divers are only familiar with their own equipment and have little to compare it with. Often, divers buy what their instructor uses and this can have a domino effect in the sense that everyone in that circle ends up buying the same kit. A point to note: professional instructors often have a financial stake in what their student ultimately purchases. This can work for you or against you. An instructor seeking a profitable, long term relationship with you will not sell you anything inappropriate, except by genuine mistake. But an instructor may not have access to the equipment you want, may prefer to palm you off with slow moving or more profitable items, or is just trying to impress you with his or her superior knowledge. If you choose to ignore advice, then you have only yourself to blame if you are dissatisfied. Some sales people will direct you to a competitor if they either don't have what you want, or if they feel your decision is so far off base, they'd prefer not to make the sale rather than compromise their own ethics.
Long-term aftersales is very important and sometimes overlooked. Dive retailers are quite used to people crowing about how they've bought their gear more cheaply overseas. Often, the case is that they end up with equipment from obscure manufacturers, whose range is not imported into their home country and for which no spares or aftersales or service are available. International guarantees are useless if no one exists to carry out the work. Sometimes equipment is imported unofficially (known as grey importing), which may void all guarantees. Serial numbers have even been removed on occasion to prevent the manufacturers tracking down the culprits who are supplying their equipment unofficially. US manufacturers, in particular, often refuse to supply equipment to dive stores which do not meet their standards of professional service (product trained sales people and factory trained repair technicians). Their equipment is only meant to be sold via their authorised dealerships to ensure proper customer service, and so they may very well disown equipment supplied through the back door. When you buy life-support equipment through the proper channels, you'll often be asked to fill in your contact information so that in the event of a product recall, the manufacturer can contact you directly to advise you of a problem. Regulators, computers, BCDs and even cylinders have all been subject to recall for potentially life-threatening faults.
Buying abroad can incur other problems. Battery chargers may not work with your country's voltage, instruments may read unfamiliar units, leading to confusion for you and your buddy, and regulator-to-tank connectors may vary. Cylinders must meet specific legislation which is not universally agreed, even within the European Union. This can cause problems with getting fills and testing if the tank is exported. Some countries are locked into providing air fills at 200 bar (3000 psi) or less, which can make it very hard to get a foreign cylinder filled to full capacity. A 300 bar (4500 psi) tank filled to just 200 bar (3000 psi) may not hold enough air for a safe dive.
