Better ?, depends on requirements, the shorter overall length of the 4wd manifold is less laggy than the 2wd, but becomes a limiting factor above a certain level to power, esp at the top end of the rev range.
The 4wd manifold does not use a damper ?, it doesn't need one, the way the 2wd turbo is mounted and the design of the trousers is the reason the 2wd needs a damper, it effectively acts as a lever, the damper was not put on by cosworth, but by southampton university who did the NVH on the engine when developed, certainly if below 350bhp I wouldn't bother with a 2wd one personally.
tabetha