ColdCard Q Security with self-rolled seed as pure signing device

Hi everyone,

so after the Coldcard dilemma I self-rolled my seed using dice (and only picked the 24th word using the suggestion from Coldcard Q when entering the 23 other words) because I also don't trust the new Coldcard Firmware from those scumbags.

So I'm still on the old firmware. I know the RNG and some connected functionality (like Paperwallet) is vulnerable, but I only want to use it as a signing device for my self-rolled seed (with passphrase, btw).

The only way the seed would be vulnerable (imo) is if the Coldcard's QR Export to Sparrow Wallet (which I'm using) would somehow export the private key as well, which is probably highly unlikely since Sparrow Wallet is not controlled by Coinkite (and I'm not even sure if Sparrow Wallet supports getting the private key that way).

What do you think, is the Coldcard Q secure as a pure signing device? I might take a look into the Coldcard Firmware Codebase again, but the last time I did (just quickly) I couldn't find the function for the Sparrow Wallet export.

Unfortunately the other HW Wallet I had (bitbox) died some time ago, and also I really like the keypad on the Coldcard. It's unfortunate there are (almost?) no other Wallets which have a keypad like that.