The Sony DW-G120A is the same drive as a LiteOn SHM-165P6S.
Whether it’s an overpriced LiteOn depends on your definition of overpriced; here in Denmark the Sony costs roughly 5% more than the LiteOn, which I consider to be a negligible price difference.
If you don’t care about warranty, a Sony DW-G120A can be crossflashed to a LiteOn SHM-165P6S and vice versa.
I actually bought a Sony DW-G120A myself instead of the LiteOn, because one of this forum’s experts on LiteOn drives said, that in his experience the Sony drives had slightly better build quality than their LiteOn counterparts.
This could just be a random experience based on a few drives, but I didn’t mind paying 5% extra for the chance of getting a better build quality. Whether you believe in this quality difference or not is up to you.