Considering its free, you can always use it if you feel the need to use one. Like for example, many swear by another sandbox by the name of Sandboxie. I personally think its overkill to load the system with products to plug in any possible hole in the system.
I am more of a 1 to 2 solutions max user: i.e VOODOO SHIELD + WD; Kaspersky + VDS, etc.