Their assets are fine, I suppose if you like the character styles. They do give the source files to be animated and customized which most don't. If you need more characters than what comes with Articulate 360's content library you could try E-learning Art.
I usually go to deposit photos and search for a character and they usually have multiples. Then I only need to buy want I want.
As an FYI, AppSumo often runs these specials on Deposit Photos which are a great deal when they come by. You pay pennies for images. Unfortunately, they just had one end, but you can sign up so you get alerted when they offer it again.