that seems pretty outrageous, you should have requested to speak to their manager. I would do so if i were in your place.
Asking you to trade in for a different sounds like motorola is trying to suck your - well maybe mine too since I now own a MS - money.

Let's hope i wont have any problems with my MS.

yup they might throw you a one for one replacement if it gets to the media.

I think i bought from the same shop, i was told that during the 18months i will get a 1:1 replacement if there are any hardware issues? is that not true?