ESEA are known for their bullshit, they once installed a bitcoin miner in their paying customers clients without disclosing it ? (https://www.pcgamer.com/uk/esea-accidentally-release-malware-into-public-client-causing-users-to-farm-bitcoins/)
Valve on the other hand, well VAC sucks, I am/was a big CSGO player, I've played over 5,000 hours on my two main accounts and cheated on smurfs for the banter, never been banned on my main accounts.