I doubt it would work, I love sorting Lego, I find it quite therapeutic. There are too many variables in lego pieces to check for a machine to do it sufficiently well. I usually sort just one type at a time, such as flats or 2-by pieces.
Having spent the afternon painfully trying to rebuild a police station amongst a firestation set and other random lego mixy sets all broken into one big blue tub i am slightly foggy minded with words inmy head like flat twoey and fat fourey and little sloped light arghhh - so i see this head shaped sorter thing in smyths for a rip of £35 and wonder is it any good or is it just a pile of sh**? Anyone got one to advise because if it did the sortign i would be impressed?