using MacConkey agar for "red/white" selection

[Viraj]

Hi Netters,


I wanted to order some MacConkey agar for red/white color selection of
recombinants, but noticed there are several different kinds that one
can order from Difco.  Does anyone know which catalog number is the
correct one?

Additionally, I faintly remember a post a several months ago where
someone mentioned that Beckton Dickinson sells a product called
"MacConkey-II lactose agar", which does not require plating with IPTG. 
Has anyone had any success with it and if so, where do you buy it from
(vendor, cat. number, etc)

Thanks,

Viraj
Dept. Org. Biol. & Anat.
Univ. Chicago