Since nobody spends much time at the top end, I think a better question to ask is: How does the gear change affect the rpm of the engine at a given speed. Increased overall rpm for daily driving will tend to decrease fuel economy and increase engine wear. Performance has it's costs.

So, at 55mph, with the stock 4.1 gear, the RPM should be just about 3000. At 65mph it's about 3500, and at 75 it's about 4100. Just for the sake of comparison, at 160 it's about 8700.

With a 4.57 gear, 55mph = 3300, 65mph = 3900, 75mph = 4500, 160mph = 9700 (nope).

With a 4.77 gear, 55mph = 3500, 65mph = 4100, 75mph = 4700, 160mph = 10100 (nope).

The following notes are provided for the more scrutinizing members among you:
- All rpms above were rounded to the nearest 100
- Numbers are calculated, and may be off by +/-100

 

^ you have a good point but here in california in normal day to day driving it's less likely to happen all the time