Nick -- you might check out GoLite's Shangri-La 3 (formerly known as Hex 3).
Per the GoLite website, the total weight of the Shangri-La 3 is about 4 1/2 lbs (fly, inner nest, pole, and stakes), and that can be reduced a good bit if you're already carrying hiking sticks -- use the sticks lashed together (or just use one of them with an extender) in place of the provided pole.
Here's a link to the Shangri-La 3 page at Go-Lite's website:
Here's a review by BPL staff of the Hex 3, the former version of the Shangri-La:
Many other reviews can be found here at BPL's website -- enter "hex 3" in the search box at the upper right corner of BPL's web page (and might also try searching BPL's site for "Shangri-La 3" to locate reader reviews/discussions of that current version of the Hex 3).
Plus, there are a lot of reviews (80 or so!) to be found at the "Shangri-La 3" page of GoLite's website linked above.
As it appears from the GoLite website linked above, the Shangri-La 3 is currently on sale for $249.99 (reduced from $500), with free shipping for orders over $100.
PS - if you're going to need space for more than 2 folks, the Shangri-La 5 is another option, at $50 more (plus a bit more weight at 5 3/4 lbs).
Here's the link to the Shangri-La 5 page at GoLite (out of stock til May, tho):