They work well. If you pull them you may need to make or buy a puller to lever them out of the ground. I do not consider them disposable as I would not want them to get caught up in farm equipment etc..
If you were setting the same spots every year and they are not a problem to leave, I could see leaving a few in the ground.
off all the designs, I do not really like the "bullet" design as it is heavier than the flat metal ones and the socket holds dirt and the driver gets stuck in them sometimes. You have to keep the socket clean of dirt on those.
The stake driver you use is important. Buy or make a good one that will hold up to hard use and will not mushroom or bend. Carry an extra stake driver or two in the vehicle as it becomes yet another tool to forget and leave at the set. Painting them and your hammer with orange or red spray paint is a good tip.
If you have a hard rocky soil to deal with they can be hard to get in and hard to get out, but then so is rebar in that situation.
You will need to experiment with cable length based on your soil type. 12" may work or you may need 15" to 18". Should almost never need more than that, perhaps up to 24" for pure sand.. Make/buy a driver that is a few inches longer than the cable length.
Overall, I would recommend them over rebar only if you are walking/carrying in equipment or trapping in very soft or sandy soil where only long double staked rebar would hold.. If you are trapping off a truck or ATV, there is little advantage.
Different strokes...buy or make a dozen and give them a try, you may love them.