We travel from NH to CA every year and have no problems going through El Paso on I 10, as long as you are going through before or after rush hour and stay in middle lane. Best day is Sunday, no where near as much traffic. As for Atlanta lots of traffic but if you hit it the right time, going right through from I 85 to I 20 saves a lot of time, just have a good navigator!
Going around there is a lot of truck traffic.
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