The Best way to View the Clips would be at 100% Zoom or Less.

At 100%, there is No losses due to upscaling.
at less than 100%, the size is smaller, but still no loss in crispness or clarity.

720p clips can be Zoomed 110% - 120% without Significant losses.
Above 120% you will really notice it.

1080p clips can go to 140% befor you notice the same amount of loss as 720p at 120%

But Any time you Zoom above 100%, there is Pixelization. New Pixels have to be crated from adjacent Pixels, and this cause loss of crispness and clarity.
Edges get Jagged.
and the Higher the Zoom, he More Boxy it will stat to look.

With all of the above information to Digest..

My Recommendations:
Consistent Size Not Important to you..
If your Screen size is 1080H or Less.
Use 720p size cards at 100%
or Use 1080p size cards but reduced the desktop zoom to 80%
place a check mark in the reduce to my Screen.

If your Screen is 1200H or More
Use 20p and 1080p cards at 100%
(you might even want to got to 120% Zoom
and then also check reduce to my screen.

I'm happy to still see the Different Sizes of Standing clips on my Screen.

But if you want to see consistency in Standing clips,
The Use the Other two check Boxes

Consistent Size is Important:
Screen is 1080 or Less
Don't use Adjust to 1080
But Do use Adjust Lower to One size.
And also Reduce to my Screen
Zoom at 100% or 80%

Screen is More than 1080
Use all three
Adjust to 1080
Adjust Lower to One size
Reduce to my screen
Zoom up to 140%

• Since you are Upscaling to be Consistent, Some clips will show Pixelization.

Thanks for your help WA i adjusted my screen resolution and right now i'm going with option four to check all boxes and i'm going with a 130% increase, i like my close clips to be just as big as my standing.

I do not see any of these advanced controls on V1.1.0.86.

>> We added a few extra control in advanced settings so everyone can tune the different sizes to its taste.
>> "Adjust all clips to 1080p in full size"
>> adds a bit of extra zoom to the 720p clips when played in full size, so the girls filmed in 720p and 1080p have the same height on your screen

>> "Reduce clips to my screen resoltion in full size"
>> reduces the zoom for a clip if needed so the head of the models are never out of screen when standing up in full size

>> "Adjust lower resolutions clips to one size". New 720p and 1080p feature the same size on your screen for the models sitting or standing up.

So I am losing the heads of 1080 clips standing.
My screen resolution is 1080p. I like big, so I use >100% size. Perhaps that is my mistake.

Can somebody please assist?