Oh you’re talking about AdGuard VPN not solely the main AdGuard product. Definitely not ideal. It doesn’t offer the same level of features as my current VPN who offers ad blocking anyway. Not to mention a few suspicious quotes from their website:
AdGuard VPN protocol uses the most secure and fast encryption algorithm to date – AES-256
From the very outset, we resolved to develop and deploy an in-house VPN protocol instead of picking a canned solution — that’d be too easy
We are going to make our protocol implementation publicly available in the future. Sadly, right now we don’t have enough time to prepare the project
we collect data about how you interact with our services, how much traffic you’ve used, and for how long have you been using our services
ADGUARD SOFTWARE LIMITED is a company registered in Nicosia, Cyprus, registered office is at Klimentos 41-43, KLIMENTOS TOWER, Flat/Office 25, 1061, Nicosia, Cyprus and acts as the data controller when processing your data
Considering Cyprus telecommunications laws it doesn’t seem like the safest place to headquarter a telecommunications privacy company.