We recently built a concrete block wall and used a bag of this to make sure that each block was level before gluing the blocks in place with construction adhesive. It worked well for this although there are some smaller stones in the sand which you need to look out for so that they don't stop the sand from compacting properly between the blocks.
We also used it to add some extra ballast to a bag of Quickrete cement for the foundation we laid for the wall and it was perfect for this too.
Good general purpose sand, easy to use on a building project and excellent value for money.
Pros: Easy to Use, Easy to Work With, Economical, Performs Well
Cons: contains some small stones