I'm not sure if this helps, but I bought a 5 sample pack from a well known vendor a while ago, and they were ALL terrible. Tasted nasty, like chemicals. I couldn't even.
However now, some 2 months later, they're quite nice. Whenever I get new ejuice, I take the lid off the bottles, stand them in a bowl of pretty hot water (not boiling, you'll melt your bottles) and let them cool to room temperature. Give them a good shake and leave them to sit for a couple of weeks. Some people say leaving them in the window where it's warm helps, but I prefer to store them in the dark. This has made a huge difference to my vaping. Alot of people make the mistake of trying to use their liquid as soon as they've bought it, and get that terrible chemical taste.