I think the $130 estimate is too low. Batman is a much more popular license than TMNT, and the TMNT 1/6-scales shown so far have also been all plastic for $150. I would guess at least that much, if not $160-170, for Batman.
I know prices are rising across the board, so to some those prices will be reasonable, especially compared to the custom route. But it's also worth remembering that Mondo has yet to deliver a quality figure. Everything looks perfect; accuracy and likeness are all there for the Iron Giant and TMNT figures. But the one figure they have released, the Iron Giant, does not feel solid and has some questionable design decisions. For great quality, likeness and paint, I would pay $160 for an all-plastic Batman. I hope they deliver.