I picked up a pound of UNIQUE last week and when I tried to setup today with my Hornady powder measure, ...
You did not say if you were using the Hornady powder measure on a progressive or not.
Assuming you are not using it on a progressive, yes Unique can be difficult to get to measure consistently.
For batch loading on a single stage, I throw 20 or so charges before attempting to weigh anything. it settles the powder column. Any powder, not just Unique, but definitely dificult to meter powders like Unique.
I like to use a powder baffle in my drum style measures with the axis for the holes of the baffle parallel with the rotational axis of the drum. Therefore, the holes in the baffle do not directly line up with the metering cavity.
I cycle the powder measure the same way every time to minimize variabilities. I prefer to not induce any more vibrations than necessary, but some like to wrap the powder measure at the top or bottom of the stroke. The key is to do it the same way.
On a progressive, the vibrations of the progressive operation adds some difficulties. The height of the baffle may have an affect here but I cannot say form sure. Some folks have luck with the baffle half way up the reservoir.
Still, operate the progressive the same every stroke so the powder measure experience the same vibrations and inputs.
While I will not dismiss the Hornady powder measure on my L-N-L progressive, I did modify a Redding 10-X for use on my progressive and it works very well.
And, yes, the Lyman 55 has a good reputation of throwing consistent charges of Unique. (I have not used a Lyman 55, need to correct that one of these days.) I have a Dillon SDB progressive and the Dillon powder measure does a good job with 700-X, a similar flake powder as Unique.
Hope this helps.