A paid service might not necessarily be safer or more secure than a free one, but usually when you pay for a service, the tier for which you pay gives you a guarantee for some sort of level or tier of service (for example, a certain amount of bandwidth or speed on a VPN such as this one) and the service provider is more dedicated towards maintaining that tier. Of course, this is going to vary depending on who we are talking about, but given what I know so far about WhoAmI, I feel good about purchasing from them.

Feel free to PM me once a paid version is out!