What is the difference between various VM solutions?
As you've pointed out, there is plenty of virtualisation software. However, the most famous are Parallels and VMware Fusion (the other ones I haven't used, so I can't give you an opinion about them).

In my opinion, Parallels is the more robust one and gives me the best performance. There are a lot of online battles going one between both camps and there both apps have their (dis)advantages. For me, Parallels is the best way to go, because it has the most functions.

For most people it's a close race and they let the price decide. Both companies often hold special sales, so you should look for those kind of things.