I don't see this card as having an impact, not at $10-$20 less then the non light version. But the data presented here of course does not give one enough information to make an informed decision.
What are the "nitty gritty" changes that result in the reduced performance / price ?
Same 6 +2 Phase power design ?
Same Hi-c CAP / Solid CAP design ?
Same Super Ferrite Chokes ?
Same Thermal Pads and Contact Plates on PCB Memory, Memory Moffset, Power Circuitry, VRM Controllers ?
These design / construction features are what separates the MSI 970 from the other vendors and if these are dropped for the cheaper price, then much of the reason to invest in the MSI disappears.