we have and found them to be vry usefull. Use it on our Tyzac Zyto
which doesnt have a gaurd so to speak as its so old.
Mind you I would only use on a heavy saw and would never use on a saw with a break.
Also do you have enough arbor length to carry the Dado head, even on the tyzac which was made well before the currect guidlines for not being able to fit dados the arbour is to short to use the whole stack
If your still interested and need a dado head 30mm arbour pm me as I have I bought one in error andlost the receipt so coudnt change it.