Natatorium Roof: Stainless TEK Connector - 410 versus 316

[STR04]

I'm no metallurgist, but my take from this old thread is that the 316 is far superior from the 410 for corrosion resistance.

http://www.eng-tips.com/viewthread.cfm?qid=330465

I guess the advantage of the 410 is its hardness when tapping into metal so I can see its advantage over 316. I'm not sure you can tap much with 316. My problem is that I'm looking to install TEK screws in a natatorium roof (deck+framing with access to one side only)which is one of the worst environments for metals. The metal being tapped is a total of 3/8" thick...ouch so I'm not sure if this can be done. Has anyone used a 316 toggle bolt?


Here are the two products I've found for 410 and 316.

http://fastening-solutions.itwbuildex.com/Asset/410SSTeksbonded.pdf

http://www.sfsintec.biz/internet/sfsinten.nsf/PageID/SX_RC