I've heard a few criticisms of Ken Ham's creation evangelism,
i.e. a kind of look at this YEC evidence for a YE
therefore become a Christian
with very little gospel mention if at all.
Definitely a subscriber to Richard Bube's "Science Demands Christian
Danger comes if someone begins to question their YE stance, since this is
an important bedrock for their faith.
Ken Ham is certainly an eloquent and passionate speaker, but I don't
admire his methods or his message.