Don't worry my friend.
-3 means u have a silver version and -2 shows that u have a black model.
This VLCDS number is as far as I'm aware the internal product code from ViewSonic and the VP191s/b had already last year the VLCDS number with -2 for black and -3 for silver. Last year the model had 16ms.
What I learnt from the different forums (most of it here @ PRAD) the 8ms can be identified by the sticker on the carton and not by the VLCDS number, at least for the 19 inch version.
Hope this helps.
BigRed