I don't know if this question really fits in here, but I shall ask anyway.
I have one of those air fresheners in the car that go on the air vent. The refills you buy in the shop are all so synthetic and the choice is limited.
I decided I could just as easily make my own using some nice essential oils.
I just wanted to ask a bit of advice, Do you think an oil base or a water base would be more suitable? I was thinking that a water based one may evaporate too quickly.