[Leica] Best Solution for M10 Viewfinder Maginfication

[frank at f3documentaryphotography.com (Frank Farmer)]

Team,

I was annoyed to learn that the M10 does not accept the older screw-in 
viewfinder magnifiers (1.25x and 1.4x). As my aging eyes don?t achieve 
tack-sharpe focus with a M camera and a wide-open 90 Summicron like they did 
when I was in my 20s, I feel I need some help. 

Here are my questions:

1) How does the Leica viewfinder thread adaptor work? I looked for a video 
on the subject with no luck.

2) Is the viewfinder thread adaptor bulky? Cumbersome? Does is otherwise 
hinder the viewfinder when not using a screw-in accessory? Does one leave it 
in all the time?

3) Are the two lines of questions, supra, obviated by the newer Visoflex? In 
other words, does the Visoflex allow magnified focusing like using live view 
on the M10 such that the viewfinder magnifiers are not necessary?

Please advise. 

Thanks in advance,

Frank F. Farmer
Jackson, Mississippi