What type of progressive:Nikon i or Varilux comfort?

[volan]

Hi there;

I was wondering if someone on this board could help me out. I currently have 2 pairs of glasses. One is a general wear pair and the other is an office/computer pair. Both are progressive with + prescriptions on top and bottom and with astigmatism correction.

The general wear pair have a depth of 16mm and have Nikon i lenses in them. The computer wear glasses are deeper and have Nikon on-line lenses in them.

Now it's time to change my prescription and here's where my dilemma is. I'd prefer to hang on to my current frames (and save the money of buying new frames) because my frames are in great condition. My general wear frames are Flexons and I don't know what the other is. My optician is suggesting I change from Nikon i to Varilux comfort. Her reasoning is that the Varilux has a larger intermediate and a larger reading area, but you need a minimum of 18mm depth which means I need new frames. But my optician says that she can't guarantee that by purchasing the deeper lens I won't need an office/computer pair. The intermediate/reading area may still be too small for 8hrs a day of reading computer screen/printed documents.

I'd like to know from people on this board if there is an appreciable difference between the Nikon i and Varilux comfort with respect to intermediate (for computer screen distance) and reading (for printed documents). If so what are the differences. Does anyone here have a recommendation?

Thank you for your help.