Tried Varifocals for several months but had to bend my head down to see obstacles when walking which gave me problems with my neck; one also has to pay particular attention when driving and using the door mirrors.
There was also the problem that I had to turn my head when reading as except for the distance part the field of view in focus was very limited.
Bifocals were much better in both respects - the distance part of the lens cut off was lower and the field of view in the reading prescription part of the lens was wider.
On both occasions I had two pairs - one plain and one polaroid sun glasses.
Unfortunately the reading prescription was set at 30cm in my normal glasses which is too close...the Shades I had made with a focal length of 50cm.
I still alternate between carrying three pairs of single vision glasses.
I've also lost most of my power of accommodation.
I should add that although I still fly I don't fly commercially any longer so maybe this is a "thread drift"...
good luck