I'm using VPC.
That's interesting as you can use an other OS without installing it on your hard drive.
However, there are two problems :
- it's slower than a real installed OS (even with a good computer)
- the "Alt Gr" touch doesn't work (as it is used to exit from full screen, to come back to your main OS...) and it's very boring when you want to use ~#{\ ...
I think that it's a good way to try a new OS before installing it, or to try your programs on different OS (if you are a software creator).
I tried the other one too, but it's less efficient...