Given the starting "plus" of that sentence, it's obvious that the author's concern isn't so much the energy savings of the newer bulbs over the older ones, but

Given the starting "plus" of that sentence, it's obvious that the author's concern isn't so much the energy savings of the newer bulbs over the older ones, but the improved quality of light over the now aged bulbs. With that much yellowing on the older bulbs and a per-bulb price only 1/9th of what it used to be, I'd replace them too without a damn about the electricity savings -- that they would lead to any savings at all would be a bonus.