the arsenals are better built, or at least a bit nicer. They look better, have better fit and finish, and they are build in Russia, in the same factory/assembly line as the full auto military version AKs.
Aresenal brand guns as we know them in the US, used to be made in Bulgaria. What I consider an Arsenal brand gun is Bulgarian. The rework of Russian Saigas is a new thing.
Paint on numerous Bulgarian Arsenal guns is poor quality. I've had a few, and all of them had paint that was damaged by Hoppes #9 and other gun solvents. The finish on my SLR-107UR was the worst one, the paint would come off easily with Hoppes. I had that whole gun refinished. I've also had an SA-93, SLR-95MB, and SAM7. The finish on all of them were weak, the 107UR being worst, SAM7 second worst and the older ones seemingly better. The Arsenal guns are for sure better assembled than WASR's, and the finish looks better when you first buy it, but the paint they use sucks.
I suggest a MAK90.