Apple maps with car play is fine for cross country trips. It seems to be a little slow for use with complex interchanges interstates with congestion. Multilane streets and highways around Cary NC were a problem.
You’re correct about 4A on dry or wet pavement. But not the same as 4H. In heavy snow, 4H will feel more stable.
In winter I use tires for ice and snow (Blizzacks, Ice Gaurd, etc) because slush and ice is more of a problem where I live.
Use 4H to get out of 4A problems. Use 4L to get out of...