Never had a 7 mill before all ways dove a 3 or 5mil maybe down to 65°. I figured a 7mil farmer Johnwould be more versatile if too hot I could leave the top off. Willing to try 60s if I can find someone to dive with? 50s maybe if I am comfortable in the 60s. 40s I would have to learn to dive dry! Hope to try it 5° lower at a time, if I find a willing buddy?