IK Multimedia Z-Tone Buffer Boost

I use it in my pedal board at the end of the drive chain and into the front of the valve amp and it does the job, nothing crazy but improves the overall sound and you can also boost it and shape the sound very quickly so can play around with it depending on the song with a toggle touch and the shape. Very good construction too. It does a subtle thing but definitely in a good way. I have not used the DI but again is one of the good extra features you get with this pedal.

Don't expect dramatic changes in your tone. This is subtle but the little it does sound really good. Useffull if you want to match the sound of two very different guitars.
The DI out (XLR) is too hot to be usable. It manages to clip the input of my interface, even at nearly minimum gain (UAD Volt).