VANOS maps - Cobb vs JB4 back end flash vs stock

I look at the stock map and it''s got some strange changes as revs change, maybe to do with intake manifold harmonics. The JB4 back end flash uses what I think looks like a good start point based on what it should look like theoretically (lots of overlap down low with overlap decreasing as revs increase) and has more aggressive overlap down low than stock. I've never seen a Cobb map (really want to).

There must be a reason why the stock VANOS map looks like it does. I'll post pics wen I'm back in front of a real computer.

Anyone have any thoughts/experiences using different VANOS maps?