I have never tried T-5's so I cannot speak from experience about them but I have tried 6500K CFLs and in that case the nodal spacing was not as tight as my HID light using a 6500K bulb and the growth was slower, and I more than gave them enough CFL's to do the job.
Each type of lighting has it's own use and for some, depending on their situation one might be better than another. In this thread it was asked if it wold be better to veg with a HPS of a T5. Well HPS puts out a light spectrum that is best for flowering, not vegging, so that right there makes the HPS not all that desirable for vegging, period, thee end. But the assumption people made about the T5's was that they would have the 6500K bulbs and not the 3000K bulbs that can be used in them or mixed with 6500K bulbs. If the 3000K bulbs the T5 would not have much of an advantage over the HPS, the light spectrum would be similar enough to a HPS that it would not be a real plus. If that were the case a HPS light using a MH conversion bulb would be a better option because that would give you 4500K, a more blue light spectrum than the 3000K T5 bulbs would give.
So people all went on the assumption that the T5s would be 6500K and the HPS would be around the 2100K they tend to average. If the assumption is true, the T5s would be better, at leas for shorter plants and then later, if vegging tall, a HPS with a conversion bulb (if it is a magnetic ballast) would be good to go to. But if the HPS has a digital ballast and can burn a 6500K bulb, the HPS using a 6500K MH bulb would be superior.