Agree! I'm zone 5b, which has an average minimum temp of -10 to -15 F, but last winter we hit -30.
Northern Splendor is rated for zone 4, so might be able to handle that deep cold better.
Also this cultivar is supposed to have a good fiery red fall color and apparently goes dormant earlier---so I hope to be able to enjoy the fall color without a sudden early deep fall freeze knocking off green leaves and causing branch dieback (which seems to occur commonly around here). Northern Splendor has somewhat upright branching, too, which is a positive for me.
