When I was waiting for my Bacstat water I asked my pharmacist if he had some. He gave me sterile water for injection and said it would work all the same..
It did not. The injections were painful, with a burning sensation and after 8 days of use I felt no benefit what so ever (yes I probably should have stopped but it didn't kill me and I wanted to know for sure so I wouldn't make the same mistake again in future). The next batch I reconstituted using bacstat water and within days I was feeling the benefits, with no burning or pain during injection.
From my experience I will only be using bacstat from now on and would recommend the same, however buck1973 seems to know his biz, so your call.
good luck.
cheers