Since fluorescent lights create more or less effective light due to the shape of the bulb, that has to be taken into consideration when figuring out the wpg. T5's should be multiplied by about 1.2, and the screw in type CF's are about .8.
Well not sure where this info comes from, but I do believe that T5's are better, no doubt. Its not just the shape of the bulb, its also the lumens per watt delivered or efficiency.
These 1.2 and .8 numbers. how were they measured? Also the .8 number what orientation of the bulb was used in this test? The bulbs are designed to be used vertical, many aquariums use them in the horizontal position which I believe is less efficient(maybe not). Also since they are larger diameter bulbs you need to use larger diameter reflectors/fittings, which is very hard to do in the horizontal position how many aquarist like myself use them. On the T5's tested what kind of reflector was used? The higher end fixtures have a much better reflector then the Coralife("average" reflector), so that needs to be accounted for also.
They are just guesstimates, just like WPG. If your going to try to get technical you must provide some better information. Your better off using the water depth and surface area to make comparisons. You cannot just say that the T5's will be better based on a simple linear approach for each particular setup. I will say that IMO the tube bulbs or T5's should do better with deeper tanks, the 29G would be the deepest tank that I would consider using screw in bulbs for.
If you are guesstimating you cannot go to decimal points to prove that T5's would be better then what I proposed, you can say that they should be about the same, that's all you can say.
I will say that IMO the coralife fixture and the method I provided would be better for a 20 long then on a 29G. I think the Current USA would be a better fixture for a 29G and non CO2 but again I dont think the bulbs on that one cover the entire width, neither does that PC coralife that was mentioned.