If you have used a OldMiniBikes AZ 2151 sprocket or something comparable, were you satisfied with the quality? I have to have whatever brand I get machined, So I don't want to get something that won't last.
I have used the Azusa sprockets on several different bikes and have not had any issues. Azusa is one of the largest importers of those sprockets. If you buy them somewhere else, it will be the same thing!
They aren't too bad, We have been using them on some 4" wheel/tire combos we have been making up since nobody makes a sprocket with a bolt pattern we needed. They run pretty true off the centerhole, which is good because we use the bearing to support/center the sprocket.
And like carplay said, its the same through most of the standard retailers, I think we bought the last batch through MFG supply.