It's just a shorter working time, you gotta be quick. People used to think that 30 min. had more time to soak into the wood, that turned out to be wishful thinking. Strength wise they are all about the same. During the winter when it's cold you do get a bit more time. I keep both 5 and 30 in my shop, if it's a small part that I can set and clamp I will use the 5, for things like the fire wall where I need some time I use the 30. Your wing should be OK if the builder was quick and it was mixed correctly.