While I-93 is stunning through the Notch, it tends to be more crowded with tourists in BMWs from Lincoln southward so definitely a more stressful drive. Meanwhile, I-89 is quite beautiful going through the mountain pass SE of Lebanon, and all of I-91 in Vermont is super scenic sandwiched between mountains and the Connecticut River, and neither get nearly as much tourist traffic. When I personally make the trip from NEK VT to the Newburyport MA area, I usually go I-91 to I-89 due to these reasons.

Technically it's a few minutes faster to get through the notch, but that is more due to the 70MPH speed limit on I-93 (which is basically a moot point anyway, since most people go 75-80 on all highways around here and cops don't bat an eye)