Most people agree that the most accurate representation of pitch speed in terms of the time it takes the ball to get from the pitchers hand to the plate is pitch speed 10. I prefer playing this way, but as was found last year if you use this pitch speed it would drastically lower the steal success rate on the basepaths.
You can see Nomo's data from last year here: https://docs.google.com/spreadsheets...XCs/edit#gid=2
Looking through the various tabs/dates if you mouse over the sliders section you can see which pitch speed he used for that tables data. You can also see the SB and CS categories and what their MLB The Show/MLB average numbers look like. You will notice that no matter what the BR Steal Ability slider is set at it does not matter, if pitch speed 10 is used the steal success rate is almost always below 45%. In reality it should be about 65%. You could only achieve this last year with pitch speed 5.
I personally would like to be able to play with the ultimate realism, meaning accurate steal numbers and pitch speed. I am downloading the PS3 version right now but I am hoping someone can test this out and see if this is still the case. If we find it to be early perhaps then we can get it patched unlike last year.