Just as quick update, the mutation rate over the last 1373396 transactions (about 8 days) for me was 0.9899 %.
I know that coinprism (Open Asset, colored coin wallet) is using an old version of bitcoinjs which create HighS, but now they fix it on the backend to LowS.
I don't think open asset account for a lot, but the malleability attack pushed services to update.