I will 2nd what mswyka said about the nylon zip ties....they work great.
If you go with rubber o-rings, definitely use the 1" ones. It could be a real struggle to stretch one much smaller over the windshield tabs.
There is another product that Dennis Kirk also carries....part # 27-818.
These rubber tabs work slick as a whistle...I like them.
But.....they are way more expensive (13.95 for a bag of 10) than zip ties or o-rings, and they seem to start cracking and breaking after about 5 years.