Metabones EOS to Nex-7 now available & on the way!

I was just notified that the adapter I ordered has been shipped. I am about to test it with my EOS 10-22, 17-55 f2.8, and f4 24-105 lenses. I only own one lens for the Nex-7 & Sony E 18-55, and I have to be sure to use it at f8-11, so it is a learning experience. I also own the Canon 70-200 F4 IS. Do I have to worry about stress on the small Nex-7 and Metabones adapter from such a long lens. I do own the tripod mount for the70-200 lens, but wondered how it might do hand held. Has anyone tried the Canon 70-200 hand held on the Nex 7 & metabones adapter? I have found this forum to be a gold mine of information. Thanks to all for your advice and comments.