I posted a similar thread about a week ago about a bitter taste from DIY. I never mentioned a supplier's name in my post but it was also MFS. I have been vaping for less than 2 months and just started DIY a little over a week ago. All of my supplies except for my VG came from MFS, and since it was my first attempt at a DIY juice, I thought it was just me.
The juice I made tasted funny and seemed to have a citrusy taste. Since I read so much about steeping, I accounted it to being that. I let it sit for a week and still no better. A couple days after making that batch, I read somewhere about Walmart's VG causing a bad taste in juices. I tasted it and it did have a sweet but very slightly bitter taste to it so I decided to make another batch from straight PG.
Since I had tasted the raw VG from my fingertip, I thought it was only fair to do the same with raw PG. When I did, I immediately got one of those "I just bit into a raw lemon" faces. In replies to my post, I was told that some people can taste the PG strongly and can get this effect. What I thought was funny was that my store bought juices didn't taste like that and I could tell by their density, they had more PG than VG.
Anyhow, decided to order a few other flavors and some empty bottles so I could sample more. I ordered it from ecigexpress and decided to give their base juice a try. I ordered 1 liter of 50/50 PG/VG and it just came in today. I put on my mad scientist gear and decided to do a few mixes. In the process, I decided to taste the raw PG/VG from them. To my surprise, it was basically tasteless, other than a touch of sweet to it. I am telling you, this is nothing like the bitter taste I got from the MFS PG.
The unflavored nic juice I got from MFS was also 100% PG. It also has a bitter taste but I didn't know if it was just the nic in it or if they cut it with their own PG. The next time I place an order for PG and unflavored nic, I will try another supplier and see if their nic also has this taste.
Is it possible for a supplier to get a batch of bad PG and they not realize it? If so, that could also explain why yours has a chemical taste. From what I understand, they do mix their own juices in house. BTW, I am not trying to criticize their products or anything like that. I have nothing but good things to say about the speed of the order I placed with them or the quality of everything else.