As to whether or not they are "the best" you'll get some very biased answers in this forum. Only you can know if they are the best fit for you. Look at the styles of the logos they've created, ask for references, talk to previous clients, see if they're really as good as they portray.
You'll find lots of designers on this board who can create "the best" logos... so it really depends on your taste, the style of the designer you hire, and having a game plan - knowing what you want will help
