I tried mine with the home made mixture of 4 parts water, 1 part vinegar, drop of salt & washing appliquéd. It was OK.
Then I bought some Lyman Turbosonic & Wow, what a difference. It transforms the results and you get really sing brass out. I use the concentrated mixture (20 to 1) so get 16 cleans for the £8 bottle, but each one does 40 to 50 cases at a go. Will see what it is like with the weaker solution some time, but TurboSonic is worth looking at.
I bought one when they first came out. To be candid I used it at first but now it is just as quick to wipe the cases with a damp rag them reasonably OK than to get the thing out and use it and have to leave them to dry to have them a little bit better than reasonably OK. I only used washing up liquid and water in mine so using just that not they aren't worth £ 20 IMHO. I think that there was a recent thread on them just this last week on this Forum?