The real quality to discuss is threat models. Even using a public-mix VPN is not going to protect against Klein-style wholesale tapping (due to packet correlation). Using your own VPN to exit will not protect against legal attacks (subscriber info will still be subpoenaed). But either will protect against revealing (to every service you connect to) your roaming between access networks - eg the discovery of who is friends from their connecting to the same WiFi.
(Also, distinguishing between "government" and "commercial" surveillance is a bit of a red herring as well. Much government surveillance is done by the "private" sector, which the government at least then buys fulls access to, if it doesn't constitute a de facto government on its own - eg credit bureaus in the US)
The real quality to discuss is threat models. Even using a public-mix VPN is not going to protect against Klein-style wholesale tapping (due to packet correlation). Using your own VPN to exit will not protect against legal attacks (subscriber info will still be subpoenaed). But either will protect against revealing (to every service you connect to) your roaming between access networks - eg the discovery of who is friends from their connecting to the same WiFi.
(Also, distinguishing between "government" and "commercial" surveillance is a bit of a red herring as well. Much government surveillance is done by the "private" sector, which the government at least then buys fulls access to, if it doesn't constitute a de facto government on its own - eg credit bureaus in the US)