Dont recommend testing with puke. I fitted (under protest) a replacement macerator for a friend of a friend a couple of years back. It was one of those jobs where you get a huge sense of deja vu, small WC compartment under the stairs, in a particular street. It turned out, they also knew someone I used to know, and my former acquaintance had dragged me round to their house a few years previously to look at a 'blocked toilet' after his dear (now ex) wife, had got herself plastered, honked her guts up and blocked said WC. I took one look and realised what the issue was, and politely declined any further involvement.
Pretty sure it hadn't worked after then until I fitted the new unit, a number of years later.