I bought many of the flavors but thus far have only tried the 555 and Fennel.
Using a tiny amount of fennel in a mostly tobacco mix added to the complexity. It did not make me think of food mixed with tobacco. I will use this again.
After seeing the concerns about strength of the tobacco flavors, I used the suggestion from Switched here:
http://www.e-cigarette-forum.com/forum/diy-e-liquid/101121-health-cabin-tobacco-flavours.html
I would normally mix with at least 40% VG but stayed with the suggested 20% and used 22% flavoring.
The flavor is very pleasing. When I started vaping a year ago, I bought a bottle of 555. I think it came from TW. It was not one of my favorites so I didn't buy 555 again until now. These days, if I use a stock flavor, I use RY4. Locally, I help many smokers get started with vaping. I always start them with RY4. I may now switch new vapers to this 555 as it has more of a cigarette taste; a nice light Virginia with peanut flavor. I think this will make a smother transition for them then the RY4. For myself, I may try adding some maltol.
Newsunshine: When your company tests new flavors, it might be a good practice to mix with some VG because most of your Western customers do.
Chinese companies use all PG as a base but most people in US, Canada and UK who mix use between 20% and 60% VG as base. Some people use all VG. We use the VG because it gives heavier, thicker vapor and some people think VG is healthier than PG. One should also be aware that most people feel that VG is a little sweeter than PG.
When we mix with VG, the flavor is weaker, thus we must add more flavor to compensate. For this reason, it would be good if the tobacco flavors were stronger.