Heroku: piggybacking safe
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I'd like to create a tiny website for my client that needs to store some confidential information (but nothing top-secret).
I've created an heroku app for this. Since I need some SSL security, I'm thinking of piggybacking, using https://myapp.herokuapp.com. I don't care for the domain name, only security matters.
Is there any reason why this would be less secure than if I purchased a custom certificate ?
Thanks !