i never really noticed any difference at all in regards to Organon sust, they all worked well(turkish, nile, karachi).
For enan, the iranians and ICN(very smooth and slightly overfilled) were both cheap as dirt and worked well. I had the Sherings testovirons from Germany I think, and they actually had a bit of a sting to them, but worked great.
I go to a trusted UG now for my test. Works just as well as any HG Ive ever used, at about 1/6 the price.