What will I notice a difference going from Michelin Defenders XT to Premier or Energy Saver?

I just bought a 2010 Prius... this is what I've noticed:

2010 Prius IV with sunroof, Michelin Defenders XT, 4/32, dry rot
- 70+mph, 48.5+mpg (car reading)
- ~60mph, 46-48mpg (car reading)

Tires at 37 front 35 rear

Braking feels better than the Goodyears

Car reading mpg at slow speeds seem worse

2012 Prius III, Goodyear?, 6/32-8/32?
- 70+mph, 46-48mpg (car reading), ~48/49mpg gas receipt calculation
- ~60mph, 51-52mpg (car reading), ~50mpg gas receipt calculation

Tires are usually at 37 front 35 rear

(2014 Corolla: not sure what tires but oh my god I hated them, then we got Michelin Defenders and it felt so much stickier... )


Premiers seem like a happy middle? But apparently the Energy Savers lack on performance? Will I notice this lack of performance?

 

*Firestone Affinity Touring