I confess that I was one of the early "TTV" adopters back in 2006 AND I was primarily a film shooter. It sprung out of a desire to use a couple non-working squareshooters (A Brownie Starflex and Duoflex) that held sentimental value for me and the love of the non-digital framing and 'schmutz' (left the mirror and glass untouched).
I had several contraptions - one to attach a digital cam for immediate results and another to attach my film cam. My 'contraptions' have been copied and modified and I admit it's funny to see what others have come up with.
Always got stares and curious questions ("what kind of camera is THAT!?") and I did find it very enjoyable, but limiting in many ways. In the end, I moved on to medium and large format and have never looked back. To each his own I suppose.