I used to buy Bolgers in bulk, for the School. Never had a problem with it.
A change in regulations meant we had to stop using it, due to the Toluene content.
We swapped to Acrylic sealer for a while, but it wasn't very good for the sort of applications we were using it for.
Thankfully Chestnut brought out the Toluene free sealer, and that is what we now use.
One disadvantage of the new stuff is the thinners stink. The smell is at least twice as strong as the original product, and will give you a headache if you don't use it in a ventilated area.