Well, after much mulling over whether or not to return the 2nd NX300 over the sometimes unresponsive touch screen, the decision became easy when the touch screen stopped responding entirely yesterday morning, and only came right after powering down and back on again.
Already ordered another, as Amazon won't do a 2nd replacement - only refund.
Though I accidentally hit order on the bundle that comes with the 2D/3D 45mm lens.
Was going to fix the order, but decided to hell with it, as I was likely to pick up the 45mm anyway, and this way I get the 3D version for pretty much the same cost to me in the end.
I just hope the new camera doesn't have any problems.