I have both Practice Practical by A.D.A.M. and Human Anatomy by faculty at the U of FL College of Medicine. I do not recomend the Practice Practical at all. It is cumbersome to use and if you don't answer exactly as the program expects, you answer is counted wrong, even if it isn't. I am sorry I spent the money on it.
Human Anatomy, on the other hand, is just terrific. I bought it through the AMA, which can be cheaper than some other places, and used it extensively. It is a dissection CD, it is meant to show you the dissection step by step and all the structures you will encounter, with plenty of explanations. It has a quiz mode and also motion segments (can't really call them movie clips) for the dissection. It will reviw stuff, including osteology and landmarks, and has also plenty of diagrams. I haven't counted them, LOL, but it says on the jewel case that there are over 6,000 pictures (all cadaveric dissections).
I also have had the oportunity to use the Netter CD and I wasn't too enthusiastic about it. The pictures are kind of small and cannot be enlarged to full screen, which makes it difficult to study from it. It may be good for a quick review, but I would not go out of my way to buy it. Having the book is much better.