Antec Mobile Products has a great track record so far for releasing very solid products. The improvements to the SP1 are fantastic and with the new options of SP3 and SPzero in the lineup there may be no need to look any further in terms of mobile audio. Metal is always welcome to enhance a product in my mind and the aluminum shell of their new mobile battery is no exception, I love the feel extremely solid feel of this product and expect it will be worth the price premium.