The price difference between the 75's and 70's is NOT what makes the 75's more economical. The 75 series tires are termed PASSENGER CAR tires and have a harder compound than most 70's. There are exceptions to all rules, but typically the 75's will last considerably longer. I have put MANY tires on 123's and 75 series Michelins is the way to go, believe me.

One other thing, on the 123 cars it is particularly important to see that the tire store puts weights on the inside AND the outside of the wheel. I learned this a long time ago, and have had tense moments with tire stores over this. Most of them have a tendency to put weights ONLY on the inside because it won't look good on the alloy wheels to have weights. Believe me on this, ENSURE that they balance them with weights on both the inside AND outside.

I have had them put weights only on the inside even after I make a big deal out of this issue as a condition of buying their tires.

Good luck,