I have not but my SIL uses Zenni with great success for the entire family (her, bro, niece).
Zenni gives you specific instructions on how to measure your pupil distance which is the measurement needed to make sure your prescription is filled correctly regardless of single or multi-vision lenses.
I have found, locally, if you are having your eyes examined by an optician or opthomologist that also sells glasses, they generally will not put the pupil distance info on your prescription as they know that is the key piece of info needed to purchase elsewhere. But, as mentioned, Zenni - at least - provides very precise info on how to do this yourself.
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