if there is not much wood,,sapwood is fine,
if you have a bigger stave,, the sap wood next to the heart wood is almost turning to heart wood,,
if you have ever looked at old osage,, the sap wood will rot off,, but the heart wood will not rot,,
I have used it successfully, but prefer heartwood if I can,, or the sap wood right next to heart wood,,,,
on a small peace with really no option,, of course go for it with the sap wood,,