[callmebison]

That's a value judgement you have to make, similarly to using any service hosted by someone else.

1) Is the potential loss of privacy worth the advantages of the service?

2) Do you trust the company providing the service?

3) Could you do a more secure job of it than the company?

It's not a service I would personally use, but I have no reason to think the company providing the service doesn't know what they are doing.