Here is a picture of the Williams on my .375 Winchester.
The only real drawbacks to the Williams receiver sight is the requirement for two screw drivers to adjust windage of elevation and the lack of a push button to remove the stem.
Lyman is a superior sight run by an inferior company.

[Linked Image from i.imgur.com]

The peep/open sight has been around for awhile. This from H-T-T February 1911 cost $2.00. A fair amount of money

[Linked Image from i.imgur.com]


Slim