Does anyone here use the “Cold Storage” technique as described in the Electrum documentation?

After researching different hard wallets, I’ve come to realize that I don’t want to deal with the possibility of back doors and attack vectors made possible by poor design or malicious actors. I’m thinking of setting up the Electrum cold storage technique using a raspberry pi 2 as the air gapped, offline signing computer. The wallet file with the seed will be on the pi’s sd card and encrypted with a password. I can easily keep the sd card hidden when not in use or just delete the wallet file when not in use. PSBTs will be transferred to the pi for signing via usb drive. The drive will be formatted before starting the transfer.

I’m wondering what attack vectors would be possible with the Electrum Cold Storage Technique. Any thoughts? Do any of you use it?