Not quite.
Either method you are restricted to a maximum of ten fields. Module build characters also have the limitation that they may only go to one of each of the three major types of school with OCS as the exception for the Military options.
It is with those fields for Inner Sphere characters that you get the lesser rebate for Module and there are Clan Sibko stage 2 modules that include field rebates.
Where those are fixed for Module characters Point Buy rebates for the full amount you invest in those skills.
