[bsou]

question for the knowledgeable: I've used AWS's ACM for my certs so far, are there any big reasons why I should be using LE instead?

[ivanr]

No. Quite the opposite, AWS automates certificate issuance for you. You'd have to automate the process yourself if you switched to LE.

Of course, AWS only issues certificates when you're using their stuff. For everything else, use LE :)

[toomuchtodo]

Nitpick: You can only use ACM with ELBs/ALBs/Cloudfront Distributions.