Hi Les,
Intersting stuff you got there.... looks like the phalaenopsis that they tend to use is P. amabilis (and depending on who u ask, rosenstromii is regarded as a variety of amabilis).
I wonder if the colours of the sarcs will come out or if the white of amabilis will be dominant in your crosses... also, what's the leaf shape like? Is it more like a Phal or the Sarcs?
The only bit of information I came across on this are a couple of pictures in Rentoul's Growing Orchids Book 4. A Sarconopsis Lavinia and Sarconopsis Aussie Gem. In both, the flowers are more like Sarcs in shape but the coulours were all white...
Well, good luck with your plants mate.
Cheers
Tim