Just finished installing my forge bpv with the yellow spring installed. Here is a quick lil review

Idle: No issues...sounded good no weird noises.

Regular driving: No flutter noticed. Once again everything was smooth

2nd/3rd pull: Boost build seemed alot smoother (20/25)

Conclusion: All in all seems like a great mod. sounds good and looks like its helping maintain boost during build up. Gonna re-tune probably in a couple weeks for 23psi and see how it does.