I am obsessed by sandwich effetcs!
The only one I've liked from a DVD is Dave Forrests 'On Holemeal', which is an amazing and offbeat way to actually SHOW the sandwich 'filling' with your card, very visual, very easy and diabolical handling!
Other favourites include Luke Dancy's 'Sandwich way dod they go', Chris Mayhew's 'Holy POD', and Karl Hein's 'Grandmothers BLT', all published in Talk about Tricks.
Karl's in particular makes use of a lovely subtlety which allows for a kickback transpo between the sandwich cards and the selection, in the specs hand!
While Sankey is a hero of mine, I am not a fan of inspeperable. I feel it's limits outweigh it's impact.
Nate Kranzo's 'Double sanwich revelation' is an unorthodox sandwich routine in that the sandwich cards are not introduced at the outset, but rather are produced face-up with a flourish, already filled with the selections. It's a cool routine.
CL