When you start to use tape for your boots, is when you start to do water. So, you don't need to use tape if you are doing Beginner Novice in the U.S.A because water isn't a question, but when you get to Novice, then start taping your boots, because water obsticles are a part of your course.
So if a water obsticle is a part of your course, then you do need
to tape your boots with Electrical Tape, not Duct.
The most common boots here in the U.S.A, for lower levels are just basic Splint Boots or Brushing Boots. Brand name doesn't matter, Splint Boots are Splint Boots and Brushing Boots are Brushing Boots.
The KEY factor, is getting a boot that is lined with neoprene. The reason being, is because neoprene has been proven through testings, to absorb some of the shock that will enter into your horses legs on landing after a fence.
You can also use a Porter Protector, I've seen this used in Mid to Upper Levels. The reason why this type of wrap/boot is popular is because they protect from suspensory injuries and tendon tears.
This is a neoprene type material that you wrap around your horses legs, and then over that you use an elastic type wrap that is called Saratoga's. Or you can use Vet Wrap as already mentioned - but make sure you wrap ontop with electrical tape.