Oscar,
I can't say much about Game Jackal because I don't use it. The others I will say are definately worth the price. I have had them for a few years now and they just work. I have never experienced any system instability in using them. They are also frequently updated as well. If I have ever run across a disk that I can't backup, I know that there will be an update to address that in a day or 2. I have been pretty happy with the support in that regard. Just the other day I updated and behold, when I login today there is another version to get now as well. They are on top of this thing. While there are freewares that will accomplish the same thing with a little more work, I don't mind paying the developers for a quality program. I think you would be happy with them as well.
My .02
Hope that helps..