Mine came in just under 4 ounces.
I like the side mesh pocket for a water bottle not because it is a fabulous pocket (it's okay), but because it's an OUTSIDE POCKET. In my Sea-to-Summit, the water bottle is the hardest thing to stow without it poking me in the back. Or, if I had no water (I often don't) or some nice flat, squishy water container in the main compartment, a snack or hat or something could be stuffed in that outside mesh pocket without having to open up the main compartment.
If you want to pack it up tightly again (child's-fist-sized), the original pocket (that in use is nicely positioned inside the pack below the left shoulder strap) is a sung fit. The mesh pocket is an easier place to stuff the whole pack if you accept it being adult-fist-sized.
I'm not keen on the BG logo (easy to cross out) or the BG color scheme (the colors are fine, and mostly muted, but it's recognizably BG), but the annoying functional effect of the color scheme is to raise the weight (over the StS at 2.4oz/68grams). It adds at least 4 extra seams, that orange piping, and the black backing behind the orange piping. A seam is weaker than uncut fabric. And weighs more.
BG versus the Sea-to-Summit:
4.0 vs. 2.4 oz
side pocket vs. none
$11 vs. $33-35
Definitely a good deal. Thanks for the tip, Kent!
So I got 3 of them. Just like the UL BPing concept "you can't eat or wear your pack so why bring any more pack than you need?", I like these for kids on a day hike (a lot of book bags weigh 2-3 pounds and that could instead be a sweater, sandwich, and a pint of water) or for young kids on a BPing trip – they like to feel like they are helping and participating and 20 liters of clothing is 20 liters of stuff I don't have to fit into my pack.
And, like the StS pack is often marketed, having one on you when around town or while traveling, lets you get groceries home, buy things on a vacation, and deal with the fluffage and mission-creep that other family members indulge in.