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It depends entirely on what car you drive. You don't say what your car is, although your forum name could be a hint - But GTI Mk4, Mk5, Mk2?
The 2.0T FSI engine doesn't have a dump valve, it has a recirculating valve. A recirculating valve is more efficient and is VAG's redesign.
If you are asking about which is "better" for performance, it's a no-brainer: Recirculating.
If you are asking about which is "better" for anything else, the dump's noise is not considered cool nowadays - At least not among this forum's community.