Don't feel too bad. You didn't have to pay insane scalper prices and now your SG Soundwave is "complete".
Bought it to 'complete' the experience. Oh well it's only $5 which is no biggie, but I wouldn't value it at more than $.25.
After all the people saying over and over it was trash, and overpriced trash at that, I'm surprised you thought things would turn out any differently for you. Transformers bondage.
I still haven't opened mine that I picked up at Botcon. I put one of the free Transheadbands headbands on Soundwave and I think it worked out much better.