The problem I think I would have with glass syringes is that I'd have to clean them in between flavors unless I had a pretty big stash of them, which may be something I eventually invest in. So far I tend to mix stuff up in sessions, just so I have everything out at once and only have to clean it up once as well. Last night, for example, I made 9 different juices and probably used 20 different flavors. Right now I'm using one syringe per flavor, marking the syringe for that flavor and then putting the cap back on it (the little plastic cap that comes with the syringe) when I'm done with it. I store them all in a gallon bag, and figure with the caps on the syringes they aren't going to get contaminated any more than the bottle of flavoring with the cap on.
I just put this out here because I was eyeballing some 1-3 mL syringes from the DIY sites at an average of a buck each and figured I could do better..yup, .17 each is better
I have a crap ton of 10 mL syringes but they are difficult to work with when using measurements like 0.2 mL.
