It's like the blockoff plates for the stock DV or the turbosmart 50/50 DV's - it sounds neat at first, but it blows off *constantly* since it's solenoid controlled.
I've been a die-hard GFB DV+ guy for many years, but when I got the FiST I used the turbosmart EM VR2 (I bought both the 50/50 and the plumb-back versions) and haven't even looked at the DV+ since. It's quicker, and you don't have to disassemble your stock DV to install it, so you'll always have your stock spare DV on-hand should you need it - not telling you what to do, just - food for thought.
I kinda liked my 50/50 (which is analogous to the DV+ VTA) at first, but it would vent while pulling forward in traffic, backing out of my driveway, every time my foot moved ever so slightly off the gas pedal - it got annoying after a while. I was too lazy to swap it out until I got pulled over for the blowoff noise, then I swapped to the plumb-back and have been happy with it since. I dug the noise from the 50/50, but I just wish it was 50% less frequent than it was. The turbosmarts don't require any auxiliary lubrication, but (at least on past cars) the DV+ needed to be pulled apart and lubricated occasionally.
Both the turbosmart and the DV+ sharpen up the car a bit and make on/off/on throttle transitions a little more comfortable, so either is likely to spice up your ride a bit. They aren't power-adders, but they do add a little "quality of life". If *all* you want is whooshy turbo sounds, you can just get a DV blockoff plate, but the stock dV is so lazy it'll be whooshing allllll the time.