Currently using a ColdCard Mk4 (it's pretty awesome with it's features, durability, and reliability) with PSBT micro-SD and a ColdPower, but looking for comparable products from other companies in terms of ethos and security for a multi-sig setup.

I have some Ledgers laying around, but for a number of reasons I don't wish to use them any longer.

Ideally I'd like to use something with PSBT (device not be plugged into a computer) and has been both OS and hardware vulnerability vetted against private key extraction (comparable at least to a ColdCard).

I'd also prefer it to be a Bitcoin only device.

For software Sparrow is my go to and won't be using software or an app that comes with any hardware.

I was looking at Foundation, but don't have any deeper insight than a surface look.

Anybody have any recommendations that they've been using for awhile and hit those checkboxes?

Thanks for any feedback!