The D-Tuna is easy to fit with your Floyd Rose or Schaller/under licence Floyd Rose trems.
Watch out though! Just make sure there is enough clearance between your trem and the guitar body!
I wanted to fit it to my ESP STANDARD V-11, but because the Floyd Rose on this guitar is recessed into the body of the guitar, there isn't enough clearance for the D-Tuna, so the slightest movement on the trem backwards would cause the D-Tuna nut to snarl on the delicate guitar body. Not good!
Because of this, I fitted the D-Tuna instead to my old Charvel Model 3, which has it's Schaller trem surface-mounted to the body.
Some say you shouldn't fit the D-Tuna to locking trems that are floating, but ALL locking trems are floating!!! There is no problem with this. "Locking Trem" simply means trems that have locking clamps at the headstock and locking clamps at the bridge, which they ALL do. These floating trems are what the D-Tuna was made for. Look at Eddie Van Halen's guitars.
However, playing with one can be fiddly, as sometimes the large, spring-loaded nut doesn't always spring back accurately into position for drop D, and likewise it is possible to not push it back into exactly the right position under the bridge to return to an accurate E pitch. A little lubricant can help with this though and it can be reliable.
In all it's a good, useful piece of kit.
