Hi and welcome!
I can suggest you to have a look over
http://all4btc.com/ , it works the same as purse.io , and their system works good and protects the buys as it should protect them.
Anyway I would suggest you to avoid using sites like this, and use them only if you have to, and never buy any important thing( such as flight tickets) or something like that, because some people use a stolen credit card and you will end up having troubles with the company that issued the tickets( as the tickets are assigned to you and they have all the details about you).
Buy with caution!