I am still using a clamshell as a second phone. When we are talking about PHONES and not mini computers clamshell is just perfect for the job. I do have an Android phone as a primary, but I do prefer talking to the clamshell.
I think Samsung made a mistake with the external screen. There was no real reason to make it 3.3''. A 1.5'' for information (who is calling, who sent that message, what time is it) would have been a better idea. They should stick to the past for the design and just add today's technology to it.