Now that you have some idea of what equipment technical divers use and why, here is a word of caution. There are many unscrupulous equipment dealers out there that might tell you using technical diving equipment is a good idea even if you have not taken technical dive training or intend to do technical diving. Beware of these dealers.
Unless you plan to dive beyond recreational limits or do decompression dives, much of the equipment used by technical divers is not necessary. For example, you could buy a snow plow to clear your drive way of snow during the winter, but a shovel or a snow blower will do the same job for far less money. Beyond that, if you have not been trained in how to use the snow plow, you just might put it through your house, injure yourself, or injure someone else.
The same is true of technical diving equipment. Technical diving equipment is for technical diving. Much of it is totally unnecessary for the average recreational diver. That is not to say that a redundant air source on a cold water dive is a bad idea; it’s not. But a seven foot hose on a recreational diving regulator, a set of wings with 80 pounds of lift, or an oxygen cleaned cylinder with oxygen compatible air on a 30 foot dive is financially wasteful, completely unnecessary, confusing to other recreational divers, and potentially dangerous if the diver using it has not been trained to do so.
Sadly I have seen several recreational divers with equipment like this who had no idea what their equipment was for or how to use it. I have also witnessed recreational divers who could not execute a simple sharing air ascent while using technical diving gear they were not trained to use. Remember the advice you were given regarding nitrox in your open water class? If you haven’t been trained to use it, leave it alone. That advice applies to technical diving equipment as well. Technical dive training teaches you to use technical diving equipment just as your PADI Open Water Diver course taught you to use recreational diving equipment. Buy technical diving gear when you are enrolled in a technical diving class, not before.