Grown from seed, these plants show a bit of variation in their spination. The hooked central spine looks neat amongst the softer looking spines.
Here is a link that might be useful:
Yes, it does look nice. Its hard to see, but does that plant have dual central spines?
This plant does have two centrals but other seedlings from the same seed batch have only one or none, or one/none on the same plant. Some start with centrals as a young plant but lose them as they grow older. I don't think they look as attractive without a central.