Actually this is avoidable, but requires some work.
Originally Posted by bOOURNS
First do this:
offset will be the true dimension of a pixel. With this you can multiply the height/width by offset and obtain always pixel-perfect borders and dimensions. Anyway this would require that every frame in the ui is treated this way to see the effect.
local offset = framename:GetEffectiveScale()/UIParent:GetEffectiveScale()
I use it only for certain aspects like nameplate borders and text offset on unitframes, since they move a lot through the ui and if i don't use this sometimes things will go wild with 2px borders and such.
EDIT: MAH FACE when i discovered that indicators on QuseUI are all oUF tags WHY I DIDN'T THOUGHT OF THAT BEFORE.