I am impressed with Let's Encrypt reputation on the whole and as a Free ACME CA specifically.
Let's Encrypt never has given me any sense of being associated with "Snake oil", they are top tier.
While CAcert I have never found to have its root certificate in any Web Browser.
I am happy that Let's Encrypt puts in the honest effort to be a respected Certificate Authority and they are Free!
Well done Let's Encrypt! Keep up the great work.
And Thank you to all the Let's Encrypt Staff.