Question : Which secure FTP (SSL or SSH) has the least performance hit

I have this link which explains things:

http://wiki.filezilla-project.org/FTPS_using_Explicit_SSL/TLS_howto_(Server)

But it sounds like there will be a performance hit on the server. So I'm not sure where to turn.

Could someone please explain what I'm getting into here? I don't want to spend hours on this to find I killed my server's performance. Is there a way to make this secure only when transmitting source files?

Will they need to configure SSL on their end to? Will I need to provide them a certificate?

Which has the least performance hit, SSL or SSH?

Answer : Which secure FTP (SSL or SSH) has the least performance hit

I think the sysadmins here prefer SFTP.  Part of the reason I think is easier deployment, no certs etc.  Some info...

http://www.codeguru.com/csharp/.net/net_general/internet/article.php/c14329
http://geekswithblogs.net/bvamsi/archive/2006/03/23/73147.aspx
http://forums.appleinsider.com/archive/index.php/t-50762.html
http://forums.appleinsider.com/archive/index.php/t-50762.html
http://en.wikipedia.org/wiki/FTPS

~bp