A few notes...
First a terminology discussion. SPG means Submersible Pressure Gauge. It only refers to the gauge that shows you how much gas (air) you have left. A "console" is a housing for an SPG on a hose that is combined with a computer and/or a compass. The word Console also refers to the whole set of gauges and the housing. A standalone SPG on a hose is just called an SPG.
The alternative to a console is a wrist-mounted computer and, perhaps, compass.
Most shops supply consoles during training not because it's better, but because it makes it easier for them to keep track of all their equipment. Most experienced divers use wrist-mounted computers and compasses because it's more convenient and more streamlined.
There is no such consensus among experienced divers on AI computers versus the standalone SPG. My suggestion would be to start with the much less expensive and slightly more reliable option of the standalone SPG. If you decide to switch later, you can bring your SPG with you on trips as a backup if your transmitter fails (swapping hoses and transmitters attached to your first stage is very simple). Your original computer can also act as a backup. A lot of people will use two computers when they go on dive vacations, because a dead computer may mean missing out on multiple dives.
Also at the beginning, your money is better spent on doing more diving than on expensive gear.
Next, new versus used. I'm going to recommend new gear, at least for the regs/BC/computer, for the new diver who doesn't have experienced divers around to guide him or her through everything. Especially if you'll be working with a local shop. The warranty and relationship with the shop will be very helpful for questions about setup and use and if there are any problems. But if the shop has used gear for sale and will service it, that is fine. Save money by going with more basic gear. The people who dive the most tend to use pretty basic regs and BCDs (or BP/W). They do tend to splurge on computers, but that can definitely wait.
I've already given you advice on the regs, except that you do want the same quality octo as your primary second stage. And to note that adjustable second stages don't work the way you think they do. The adjustment is only to avoid freeflow, it should be wide open when it's in your mouth unless it starts freeflowing, in which case you dial it back slowly until it stops. The octo can be set a little harder to avoid spontaneous freeflow if it's face forward in a current. Again, if you dunk a second stage mouthpiece up into the water, it should freeflow. Stop it by turning it over or putting a finger over the hole your breathe through.
I strongly recommend a basic backplate/wing setup. But if you do get a standard BC, keep in mind that less is more. Extra padding, extra air cells, extra D-rings, and large lift capacity all make it harder to move through the water and mostly require extra lead. You should be looking at the cheapest and simplest back inflates available. Or watch some videos on backplate/wings and get one, it really is a superior setup for most divers.
First a terminology discussion. SPG means Submersible Pressure Gauge. It only refers to the gauge that shows you how much gas (air) you have left. A "console" is a housing for an SPG on a hose that is combined with a computer and/or a compass. The word Console also refers to the whole set of gauges and the housing. A standalone SPG on a hose is just called an SPG.
The alternative to a console is a wrist-mounted computer and, perhaps, compass.
Most shops supply consoles during training not because it's better, but because it makes it easier for them to keep track of all their equipment. Most experienced divers use wrist-mounted computers and compasses because it's more convenient and more streamlined.
There is no such consensus among experienced divers on AI computers versus the standalone SPG. My suggestion would be to start with the much less expensive and slightly more reliable option of the standalone SPG. If you decide to switch later, you can bring your SPG with you on trips as a backup if your transmitter fails (swapping hoses and transmitters attached to your first stage is very simple). Your original computer can also act as a backup. A lot of people will use two computers when they go on dive vacations, because a dead computer may mean missing out on multiple dives.
Also at the beginning, your money is better spent on doing more diving than on expensive gear.
Next, new versus used. I'm going to recommend new gear, at least for the regs/BC/computer, for the new diver who doesn't have experienced divers around to guide him or her through everything. Especially if you'll be working with a local shop. The warranty and relationship with the shop will be very helpful for questions about setup and use and if there are any problems. But if the shop has used gear for sale and will service it, that is fine. Save money by going with more basic gear. The people who dive the most tend to use pretty basic regs and BCDs (or BP/W). They do tend to splurge on computers, but that can definitely wait.
I've already given you advice on the regs, except that you do want the same quality octo as your primary second stage. And to note that adjustable second stages don't work the way you think they do. The adjustment is only to avoid freeflow, it should be wide open when it's in your mouth unless it starts freeflowing, in which case you dial it back slowly until it stops. The octo can be set a little harder to avoid spontaneous freeflow if it's face forward in a current. Again, if you dunk a second stage mouthpiece up into the water, it should freeflow. Stop it by turning it over or putting a finger over the hole your breathe through.
I strongly recommend a basic backplate/wing setup. But if you do get a standard BC, keep in mind that less is more. Extra padding, extra air cells, extra D-rings, and large lift capacity all make it harder to move through the water and mostly require extra lead. You should be looking at the cheapest and simplest back inflates available. Or watch some videos on backplate/wings and get one, it really is a superior setup for most divers.