I've used docusign, signrequest, and signaturely (currently using). I like signaturely, but the only thing lacking is that it does not allow for documentation in Spanish or other languages besides English.

Breezedoc simply, and easily allows for documents in Spanish. Unfortunately, when I export the documents the exported documents have breezedoc branding as a footer. Breezedoc can have all the branding when we are getting signatures, but it doesn't make sense to have this on the exported pdf documents.