As far as we know, Dreamhost works fine with Sandvox. I just tested both FTP and SFTP publishing with Sandvox 2.2.3 and it worked great. The trick may be getting your Document Root setting correct. For FTP with our test account it turned out to be / but with SFTP it turned out to be ./. The best thing to do is to simply put in your username and password and click Browse in Host Setup, navigate to your document root, and let Sandvox select the correct path for you.
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