Back in 1989, I did a side by side study comparing 10%NBF with Zinc Formalin. 
The IHC results were phenomenal using Zinc Formalin. Many of the antibodies 
did not need antigen retrieval. I was able to stain CD4 without antigen 
retrieval, to prove my work. I was working at Oregon Health Sciences in 
Portland Oregon for Jay Beckstead, at the time. To my knowledge, they are 
still using it. 
You can contact Anatech for lots of references also.
Marianne