I like the unflavored VG 25 mg from Nicvape. I know, it's supposed to unflavored,but the VG is slightly sweeter than PG. And you can always add a few drops of a flavor you really like. I use it a lot to cut flavored juices that are really strong. Try mixing it in small 3ml or 5 ml bottles so you don't waste it. Once I started doing that, I use a lot less flavored juice.
Edit: And since plain nic juice is a lot cheaper than flavored juice, you can save a few bucks.