14K is fine, but one of the best features about T5 is the ability to run more than one spectrum of bulb. All 4 of my bulbs are different, I have 2 actinics (460nm and 420nm) a "sunlight" bulb that is 10k, a little pink, and a 12k bulb that is very white with a hint of blue. This achieves an overall white look with a hint of purple/blue, has produced great growth in my corals (including
SPS and
LPS corals) and makes the colors pop out, especially when it's actinics only for the morning/evening effect.
Not to mention the fact that the bulbs that will come with the fixture are likely to be junk, you'll want to replace those anyways.