Nice to find another australian on the list. But to your question.  I 
have used both lith film and DD over the years and they have their good 
and bad points. I work exclusively with Gum bichromate and I'm happy with 
the results from using both types of film. The DD film though expensive 
is the easiest route and I have found the results with this film are 
excellent. It also comes on a thick base which makes it much better to 
handle in my opinion. The downside is that this film has a high base-fog, 
so exposure times for your prints are longer. And the largest size it is 
available in is 10 x 8. With Kodalith I use Dektol in dilutions varying 
from 1:7 to about 1:9. Develop for appprox 2 mins. This combination has 
given me excellent gum prints. And now just to add to the confusion, have 
you considered using Kodak commercial film 4127? Use D-11 or D-19 as your 
developer. Work on using long dev times and experiment with Developer 
dilution (consider using straight) to build enough density in the 
negative. Develop for at least 2 minutes - you will probably need more. 
This is a contiuous tone film so may be a better route than using the 
lith film. Personally I would avoid the lith film if you are planning 
Platinium or Kallitype. Multiple gum prints seem to work okay with lith 
(perhaps because you build up density and contrast with each successive 
printing).
I know of a good platinum printer in Sydney - Gordon Undy (he runs 
classes and his platinum prints are good - he studied with George Tice) 
who works with an Agfa film similar to the Kodak commercial film. Contact 
me off list for his contact details.
Cheers
Hamish
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Hamish Stewart
         
Gum Bichromate Photographer
http://www.vrx.net.au/ad163/artists/hamishstewart.html
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