HTTPS, free certificates and Google seo

[Cristianpm]

As we all know, Google decided to give some weight in rankings to encrypted sites. SSL certificate providers are quite a lot out there, but there is also a free alternative (Let’s Encrypt). I've been going over some of these services and compared Godaddy's and the above certificates, and there isn't much of a difference.
The question is: using a free certificate would have the same effect as a paid one? I would rather pay for one than be punished for using a free one.
What's your take on this?
Thank you!

[Inizing1967]

One think I noticed is, they have changed the local Google listing algorithm