I recently brought crowns and had to decide between getting the triceratops mount and the white stag mount, but the HP fan in me won over (a white stag is Harry's patronus) and it looks amazing!
I love the size of it (it's just as big as some horse mounts!), it looks very regal, and I have more crowns left over after buying it than I would have had if I had got the triceratops (which I will probably still get eventually).
I'm saving the crowns I have now so I can add on to them to get a bear mount or a wolf re-skin from the crown shop (yes I know neither one of those things exist yet but I think they will, and hopefully soon.)
)