I ordered this for a trip to South America & ultralightweight domestic weekend trips. It is definitely light and compactible (though I wish the single pole would fold down one size smaller so you could fit the whole bundle into one tidy bag - as it is there is one bag for the bivy itself and another for the pole).
I received the item and set it up in my yard. I have since decided to take a larger backpack (45L instead of 32L) with me on my trip - will allow for a few more comforts, layers, space for souvenirs, and unforseen space needs. I lay down inside the bivy and it has adequate space considering how small it is. The area around teh head is actually quite spacious. The area around the feet would be, but there is nothing included to keep it stiff and upright, it kind of just flops down on you. I'm willing to bet moisture would seep through to your feet. So you would need another stake and/or some nylon rope or something to keep that area taut and off of your body.
I tried laying inside with my pack (not going to leave it outside the bivy because of weather and theft concerns). No way I'm fitting in this this with a pack (no matter what size), at least not comfortably.
Also, the material seems a bit flimsy. I know it must be thin to be so lightweight and compressible, but I can see it snagging and ruining a trip real easy. The area that pulls over the pole to keep the seam protected is a novel idea, but I could already see the stitches in the area straining as I pulled it taut, and I think they would be the first thing to go (barring a rip in the fabric).
Perhaps I'm not using the bivy as it is intended. I think a slightly bigger (and yes, heavier and bulkier) solo tent is what I need. I do wonder where people who use the spotlight bivy keep their packs. Outside with a rain cover on it?
Finally - only a one year warranty? That's a dea-breaker for me. So many other products have lifetime.
Bottom line: for ultralightweight guys who don't mind bringing an extra stake/rope to keep this thing off of your feet (and who don't mind leaving their pack outside) go for it, you'll love it. As for me, I need something bigger. Cheers to backcountry for their awesome return policy and great customer service.