>The offical line from Forge Motorsports was that it should produce a smoother gear change by stopping turbo lag.
The unofficial line being that (unless you're talking high boost applications) dump valves are a waste of time other then for accoustic pleasure. VW's will surely have a recirc valve or silent dump to atmos???!!
Also- wastegate chatter IS a problem, you'll be leaking boost each time it chatters i.e. it's not sealing so it's venting boost on each open/close cycle. Probably marginal - but all the same, losing boost.