The T5s would be better than the PCs. Watts is not an indication of light output, only the amount of energy consumed to light the bulb. A PC bulb is bent back on itself, which is not particularly efficient, as it blocks a portion of the light being emitted and causes more heat to build up. Yes, the quality of the reflectors a good T5 set-up employs are a major contributing factor in them being what they are. T5s aren't the cure-all end-all of reef lighting, but an overall better choice than PC lighting in situations where T5s can be used.