"I spent some years buying Polyurethane glue in half litre bottles (much cheaper), but ending up wasting half the bottle because of shelf life.
These small bottles of Gorrilla glue are a good quantity (you don't need much as it foams up).
Problem is the bottle. The only way to prevent it going off in the bottle is to exclude the air, and instructions (rightly) suggest squeezing all the air out and replacing the cap. Nice idea, but the bottle is not very squashy, and once the glue is half used, that's really hard to achieve.
Would be much better in a tube, for which I'd have given five stars."