Hi
I have been wearing varifocal lenses for approx 4 years. From day 1 they have been superb, have not had any problems, would not go back to bi-focal. As others have said frame selection and fitting is very important. In my case I have my eyes tested by the optometrists, but use an optical engineer who supplies and fit the spectacles, perhaps this is why I have not had any problems. My wife had problems from day 1 with hers (she purchased in Cyprus) eventually got used to them after a fashion. When it came to replacement she went to the same route as I had. When the guy saw her existing specs and frames he said they were totally the wrong frames for the varifocal lenses supplied. He made the new specs and fitted them, result no problems whatever, she was use to them within a week or so. Don't give up, as Byron said make sure you have the right person doing the supply and fit.
Cheers Con