I caution you on using wax on windshields as glass is somewhat porous & once applied, it can have a negative impact later, though blade chatter, as when the blade now wipes, it becomes a bit sticky to the shield. And if this happens it is very difficult to remove the wax from the windshield then. Only jewelers rouge powder in a mud paste and hard work can now attempt to get it now smooth again..(ask me how I know)..
Back onto blades...I like the Rain X blades as well. They were rated the highest on Can tire site.
Also in this link below in a very good wiper blade video
worth viewing !!!
Reflex Rear Wiper Blades | Canadian Tire