I would not suggest a PC light at this point. Those bulbs are getting harder to get, and they produce less PAR then a comparable T5 light. In addition, T5 will use fewer watts I believe.
Those are T5's Poseidon.
I just bought the 24" one for my 54 gal. corner . It's hands down the best lighting I have ever owned. Very easy to use, the fans are completely silent. Awesome product. I think my tank is 22" deep and I have no problem with growth. I would say my best growth is about 15" from the light. I also have stunner strips to pick up the back of the tank since its odd shaped.