Stating the obvious, the key to PEX at present is the size,...

Stating the obvious, the key to PEX at present is the size, grade and continuity of the SN/WT deposit, particularly the high grade central zone at SN. All the rest (MB development, other exploration etc) is secondary in the scheme of things at present, albeit I personally believe that MB, once developed, will be the gift that keeps on giving at depth.  

Fingers crossed the high grade zone at SN is big enough to justify stand alone development with the rest of the SN/WT deposit the cream on top!