@S.Yu:
My interpretation is that it suggests up to 15w the chip is quite efficient but once you go past that, you've to give allot more wattage for not much more performance.
@Jesse:
AMD does not care about laptop market anymore. I think they stop caring like 6 years ago? They're too busy working on next gen console soc's, providing gpu's to apple and their server/desktop business.
They've never really cared about their consumer APU's tbh. Always paired with low bandwidth memory. Then suddenly when PS4 was released, it was paired GDDR5, 8 GB of it. Take a hint, they're not interested in your money.
@A:
They're the exact same chip (just configured at different tdp's), so why would they need to be put in a different SKU? In any case, even if they were put in separate SKU's, it would not matter much. At the end of the day, real life performance and thermals matter more. You could have a laptop with a 25w version according to spec, but in practice (due to poor thermal design) throttle down to 15w or less. You could have another laptop specced at 15w, but allows you to unlock the tdp to 25w and does not throttle at all when you do so due to have excess thermal headroom.
Moral of the story, don't trust version or spec, wait for the real reviews. Trust the best implementation.