I’ve successfully used Let’s Encrypt certificates on other sites that I host and I’ve not noticed any drawbacks so far. That’s why I’ve decided to force SSL encryption on this site as well. It’s just nobody’s business what you’re reading. And it’s nobody’s business what I’m transmitting.
By the way: Plesk meanwhile integrates a plugin for Let’s Encrypt, which handles certificate renewals automatically. So using Let’s Encrypt with Plesk really is a no-brainer. Odin, the successor of Plesk, will even allow the use of LE-certificates for the mail server (which is the only thing I have to manage manually at the moment), but so far I didn’t dare update to Odin 😉