I got my first ever V1 last week and I also ordered a SAVVY unit with it for $50 extra.
I have been testing and playing with my V1 alone since they arrived but today I also connected up my SAVVY cable to the V1 to try it too.
So far I like the SAVVY product! I'm not sure if it is really worth $50 extra (you need to be the judge of that for yourself) but it is actually a really nice additional feature as it automatically quietens down the V1 for normal low speed driving around town but then it becomes loud again (automatically) at higher speeds which is when you need it to.
The initial detection "hit" volume is unaffected but it is as if you immediately had hit the mute button each time you get zapped.
Anyway, just my pennies although it is a bit like trying to explain the usefulness of the arrows to someone who has never tried them!