You see the red because the plant doesn't absorb the red light it reflects it......lower the K value (ratio of red/blue light) the more red light is present, which should allow more red light to be reflected and bring out the red in plants I would assume.
Take a look at the 8800K's color spectrum. You can see that it produces more light in the orange/red (~ 625nm +) portion of the color spectrum compared to the 6700K/10,000K bulb. Below is the 'pinkish' 9325K bulb that really makes the red colors pop. The 8800K bulb has some similarities with the 9325K bulb, but it isn't 'pinkish' as far as I know.
If these color spectrums are fairly close to their actual output, I'd get the 8800K bulb if I wanted more red to show.