Samsung Galaxy S3
Finally, the Samsung Galaxy S3 beat out the LG Optimus G on this list for one reason and one reason alone: Support.
Read: Samsung Galaxy S3 Review.
While the LG Optimus G is a great smartphone, it simply won't get the kind of support that the Samsung Galaxy S3 will get from Samsung. While the Galaxy S3 should get updates for quite some time, the LG Optimus G is more likely to meet its end before the Galaxy S3 making it a less reliable option.
Those that don't care about software will find a toss up but those that do will want to opt with Samsung's device.