I have been using Elixir Nano lights for years and have never broken one; even with tuning and detuning into alternative tunings. I play bluegrass and fingerstyle so my attack varies considerably.
I agree that the Polywebs feel strange and I personally don't like the tone but the Nanos are great.
I can't use anything else; my skin chemistry destroys uncoated strings in hours.

I have heard about the breaking G string issue on other forums so it is a known problem; thankfully it hasn't affected me.