VMware Workstation is what I use to test on various hosts - particularly easy to keep "virgin" systems. It runs nearly as fast as a native system, since I use SSDs. I also have customers that use VMs, so being able to test there is a plus.
As for VitualBox, tried it once, seemed fine. VMware people have a decade of experience over them, plus, well, it's Oracle, so you never know when they'll pull back on the access like they did with Java.