t5 bulb question

[chrisouth]

i have seen 2' t5 bulbs that say they are 5000 lumens but they arent the same type of bulb as the other 2' t5 bulbs that are only 2000 lumens per bulb. my question is does anyone know if the 55w compact 2' t5 bulb is less productive as the common 2' 2000 lumens bulb that i see everywhere ??