Would he be more willing to use them if you said you would use disposable liners with the cloth? All you have to do then is throw away (or flush if you can get the flushable liners) the liner rather than a whole nappy. Maybe try the stinky bin full of nappies angle too!
Yeah I tried this too.. I think I might need to buy one so he can actually see what I am talking about. I have showed them to him online, but he just laughs it off..