Thanks for your reviews, they are some of the best on the net, but please can you update your stress testing regime. Furmark is not a useful representation to show whether a notebook GPU throttles or not. This is because NVidia have (since the Fermi cards) artificially made their cards throttle when the Furmark.exe was detected. Because it's an artificial limitation imposed by NVidia for the Furmark program specifically, then it is not representative of whether the GPU will throttle during a gaming experience. Please can you use Unigine Heaven Benchmark to test throttling behaviour. Heaven Benchmark is really good for this purpose because it provides a 100% sustained GPU load, but in a way that a game would, it's not a 'power virus' like Furmark. This way you will be able to provide useful evidence that the card will throttle or not in gaming loads. Furmark is useless with today's GPU's, and serves nothing more than to confuse matters and provide misleading information on throttling behaviour & maximum temperatures.
(Sure, the 880M is known to throttle heavily, even under gaming loads, and this specifically would have been useful for you to investigate, but not under the guise of the useless Furmark for the reasons explained).