I'm using this mod together wie "Bob's Clock". While Bob's mod runs smooth & shows every second correctly, this mod swallows a second, in a step of 1-2 seconds.
Also, the time differs. Bob's Clock is about 2 hours and 55 minutes earlier, eg. it shows 18h05 in this mod while it's 15h00 in Bob's.
The great benefit this mod has is the fast switch between x1 & my desired speed, eg. x64.