I have one. There is a guy here on the reloading PX that makes a bushing for it (same as the RCBS). Order one. Now.
I hated mine, It worked on ball powder ok but not extruded. I programmed the dispenser to slow down sooner and trickle up but it would always throw over. The charge weights would often vary by .2 grains as well.
As a last effort I tried the bushing(I got one with an even smaller, removable sleeve in it). It is awesome now. I run it full speed and maybe 1 in 100 go over weight. I always checked my charges on a second scale but after a while I stopped doing that because the dispenser threw so good. Also read the directions and let it warm up first, steady table, no drafts, ect...
I'm not a benchrest shooter by any strech of the imagination but I bang steel at 1000yd. My 308 and 338LM have single digit SD by my Magnetospeed. The Hornady Dispenser can't be too bad.