I've yet to put this bag in the elements to test it out.  However, it packs my sleeping bag, Marmot Trestles 15, Tall, very well.  The construction is solid, sturdy, well designed, and well engineered, impressive.  I am very happy with my purchase, and anticipate that it will hold up to thunderstorms, as the waterproof rating suggests.  The seams are constructed well, and look very durable.  It's a thick bag, very solid, abrasion resistant, and appears extremely durable.  Easily totable, there's a handle, once the top has been rolled down.  The rolled down top snaps close, creating another handle sturdy enough to easily support the weight of the sleeping bag.  And there's a shoulder strap included, as well.  Packed, it stands upright.

Ordered in black, the grey is a very nice accent.  Having a bag that looks good, it's very aesthetically pleasing, superb design, performs well, is engineered well, functional, and perfectly suited for one's needs is a bonus!  Form & function both win on this account.  I am confident that the OverBoard Waterproof Dry Tube Bag will hold up to the extreme rain, and harsh conditions that it will find itself in, and my sleeping bag will remain dry, and insulating.  If you need a stand alone waterproof dry bag, this is it!