Purevpn has been seen as a pretty common vpn service that people use for being safe on the internet. Tunnel bear is okay, but the free version is not something I would use if I was trying to do serious work with a vpn. I'd much rather use something like private internet access, even though it costs a significant amount. They have claimed and have shown that they really keep your browsing and work completely anonymous which is very useful for what you need it for.
PureVPN has session limits for every 24 hours. It means you cannot use them unlimited. When you keep on breaching sessions limits, your account will be barred regardless of how long you have subscribed with them.
Tunnel bear is good with their free services. Otherwise, with very less number of IP locations, you cannot find it worth for your money.
I believe almost VPN providers has some pros and cons. It is always good choosing a service based on our needs. For that availing trail for free of cost will be the right way of approaching.