Never listened to the father--but IMHO his son was a genius with a holy voice just this side of Roy Orbison's---but with a gift for writing music/prose far better than Roy ever had.
In fact I was listening to GRACE just this morning buddy. Suprised some of the tracks on that record (esp Lover you Should have come over, Last Goodbye and Eternal Life) have never been used in a movie--it would introduce a whole new generation of fans.
I mean that record lays me to waste every time. One of my top 10 and you could not talk me out of that opinion.