^^^ pretty good price! That looks very similar to a KU Engineering manifold but that one only has 3 holes for vacuum feeds on top of the manny, where the KU has 5 vacuum holes.
I have read a bit about the cons....and they mainly are accelerated main bearing wear. there are pages of reading on the dsm sites and test info in some of them as well. but that was what it came back to in the end.{The guy that did some tests was drag racing so was pulling the engine apart regularly}
the pros are that there is a weight reduction to the bottom end which will make it rev a bit quicker.
I ended ep getting an ATI super damper ....and it is bloody heavy!!....but I have a K1 stroker crank which is lighter than the stock crank and a fidanza flywheel. I also got the light weight water pump pulleys so it should all even out :unsure: