Good to go!
It's been a while since I've purchased the Denis Wick Wah-Wah/Damper for my trumpet and it still works fine for me.
My trumpet was just too loud to play it anywhere except a stage or a rehearsal room, so I bought this damper and have been using it since and probably will for forever.
I am certainly not the best or the most sophisticated player out there, but in my opinion it is all you need.
If you are looking for a good processed and decent sounding Wah-Wah/Damper which is affordable, you have now found what you've been looking for.
Of course there are better sounding ones, but not nearly for this price.
But there is one little flaw...
The cork is not as reliable as I wish it would be. After some usage it is getting a bit whacked. Not much, but enough to notice.