I've never had WL nic. I've only had three
VZ Nic - Ordered two 120ml bottles. Cracked one open for use and put one away in the freezer. The one that I cracked open and used up was good stuff. Mellow throat hit and no taste whatsoever, which is a good thing. No smell either.
Opened up the second one months later and it had a weird bitter aftertaste. Tried it with just PG/VG, and tried the PG/VG separately to make sure it was the nic. Contacted them for a replacement and they basically said that there's no way I got a bad batch and they wouldn't replace it. I know you guys like to avoid naming names like this, but I firmly believe sharing our experiences (the good and the bad) is what makes this forum so community like.
Xtreme vaping - Hoosier pointed me in this direction after my mishap with VZ. The nicotine was good quality. It was a bit harsher than I was used to, but I adapted. Towards the end of the bottle I started picking up on a bit of an odor. My friends said it smelled like fish but I just smelled 'earthiness'. I'm pretty sure this was simply because I didn't handle it the right way.
What you should do is take out 30mls or so at a time as 'working nic' and put the rest back in the freezer to slow/stop oxidation. My whole 120ml bottle was just out in room temperature the entire duration of it's use, which leads me to believe it oxidized a bit faster than it should have. In any case, it was quality nicotine with no taste imparted and a very solid throat hit.
Nude nic - This is the one I'm currently using. Its very clean and tasteless and has a mellow, but present, throat hit. So far I'm enjoying it and have nothing negative to say about it other than the fact that some of you throat-hit chasers might not enjoy this one. Don't get me wrong - the throat hit isn't weak. It's default and nice. It's just that some of you want a mega throat hit and it isn't here with this company.
I have had similar problems with customer sevice at Vaping Zone. They basically send you a canned response telling you there is no warranty.... As if that absolves them of fixing the problem with their product.