It is very possible that some models use a different source for LCD panels. Often when a new product comes out it will have high quality expensive components. Then some competing component manufacturer will show the company their "Lower Cost" part and convince them they can be making more money on the device if they use the lower price part. Of course the lower price part is also lower grade.

If you're not happy with the silver Pronto, get your money back. Tell them you paid for a quality Pronto, and not a cheap copy. Show them the difference.

Dave