DOT3 brAKe fluid is all the same stuff as far as I'm concerned. Just don't keep brAKe fluid around too long in opened (as in broken-seal containers) for more than a few months as the stuff absorbs moisture.
Yep agree.
Dot 3 is Dot 3.
Dot 4 is Dot 4 which supposedly doesn't absorb moisture as readily as Dot 3.
Even Toyota today reccomend using Dot 3 in their systems.
I have heard that using Dot 4 in their systems can cause major havoc.
It appears to be a bone of contention like the engine oil discussion - But we're not going there!!

Dot 3 is the devil we know and I think it is the safest bet providing the container has been well sealed.