Gum Chemicals - starting out question

Hi all,

I am, after much time and agonizing, finally going to start some gum printing this fall. I have a question about some kits out there in the market, namely the one from Bostick & Sullivan and the other from Photographers Formulary.

I am mainly interested in the raw chemicals in each kit, is there a difference in quality or some other intangible? or am I better off to pick up the chemicals seperately? The paper and pigments aren't as much of a concern as the chemicals, as I am a failed painter from my university days :-)

Thanks,
Dwayne

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Dwayne Sandall
"It is not because things are difficult that we do not dare; it is because we do not dare that they are difficult." Seneca