Here is a comparison of the 16"ers with just a slightly wider tire.
Tire Size Comparison Calculator
Size 1 205/60 R16 Dia 25.7, width 8.1; Revs 786
Size 2 215/55 R16 Dia 25.3 (11.6%); Width 8.5 (+ 4.9%); Revs 797 (+11), Change in speedo at 60 mph- 59.1 mph
Potential "Benefits" of 55 series over 60 series. A bit quicker acceleration, bigger contact patch (improved handling).
Potential Negatives: Decreased mpg (hard to say how much, would be somewhat dependent on the type of tire & tread), decreased snow traction, slightly lower ride ground clearance / ride height (about 1/4").
While the Michelin Energy AS are not a bad tire, they are middle of the pack when it comes to ride comfort, handling, wet & snow traction (especially important if you live in a snow zone and don't want dedicated winter tires / rims. Both are around $100 for stock size and the Vredestein Quatrac has good fuel economy bona fides.
I'm thinking these are the two t tires for the best all season bang for the buck for the Niro
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