I visited Dr. Mo yesterday, super nice and good explanation Highly recommended!
About 4D, I think it is just an extra thing to earn money from parents not really necessary. Unlike structural scan which can tell you the problem of the baby ma But of course if you can afford, why not, but my own opinion is: I have to see this baby always once it comes to life... so I don't want to waste money to look at the 4D images (kind of scary indeed)...