@mgorny Yep, saw that… and immediately thought: "this isn't an e-penis size competition."

Only thing I use RSA for is legacy system support.

My first work YubiKey I set up as RSA4096 because I wasn't sure all our systems support ECC.

Personal YubiKey was similarly set up as RSA4096 for backward-compatibility.

After breaking work YubiKey #1, I buy a new one, and set it up Curve25519.

So far, if its ≥ 2014, it just works. Only Ubuntu 10.04 and 12.04 is a problem.