if you want to know how the gearing will feel, do it mathematically, the 600 first gear with 3.73's comes out about equal with the t-5 first with 3.08's. This is great for traction and gearing. It basically moved all the gears closer while leaving the first gear about the same with my combo. before 3.73's i couldn't keep from either bogging or spinning off the line, now it's perfect. the gears are also a good length each, i drove a friend's car with 4.10's and a 3550, the gears were too short and fourth ends too early, i don't think he can stay below 5500 rpm in fourth in the 1/4.
also, im at about 1800 at 60mph, about 3000 at 100mph, so you won't be topping out the car.