The recipe dialog (when selecting an amount to craft) allows you to click in the middle of the slider bar and directly type an amount. Please allow this same functionality on the transfer (container to/from inventory) dialog. When you have large amounts (thousands of seed or wheat) and want to transfer an exact amount, you have to get relatively close with the slider, and then use the arrow keys to nudge the value to the exact amount. It's far easier on the recipe dialog where you can just type in an exact value.
To put it another way, (re)use the same slider bar code in the transfer dialog that's used in the recipe interface.
