As the first router of a new generation, the Netgear R6300 can definitely be called a success. Granted, 1.3 gbps is still quite a way away, but there are clear performance gains compared to 802.11n. Speeds of up to 500 mbps are possible with this router, and also at longer distances the 802.11ac outperforms 802.11n comfortably. You should bear in mind that 5 GHz still is 5 GHz, and a concrete wall will always be a concrete wall, meaning that 802.11ac doesn't necessarily improve the maximum range of the signal. 802.11ac is most effective on 5 GHz and at relatively short distances, but with a much higher bandwidth than the 802.11n, also at longer ranges.
Slow computer got you down? Maybe a hardware upgrade should be in your cards, if so this guide to the Fundamentals of Upgrading a PC is an invaluable read. PCSTATS Tips