AirVPN has a good price. Distrust any statement that says "No monitoring nor logging of activities online".
They write "Q: Do you keep session logs or any other kind of logs that can be used to track identity and Net activity? A: No, we don't keep logs of that kind." Notice how they make the question very specific! This is intended to slightly mislead.
The privacy statement admits "Air servers and software procedures acquire only personal data which are strictly necessary for the technical functioning of the service, for example IP address." I don't see anything that says how long this data is retained.
SwissVPN is also very cheap at 6 CHF. TorrentFreak reports that session IPs (not visited content, websites, mail, etc.) are being logged for 6 months.