I have both the tall and the standard. It all comes down to use.
The standard is noticeably smaller in practical use. It packs down a couple inches shorter and is a bit narrower. It is perfect for glassing with binoculars or angled or straight spotting scopes while sitting. You can also use an angled spotting scope while standing, not something I do much, but it does work. I usually will take the standard if I am going to be carrying my 10s (primarily for handheld use) and my 55 mm angled spotting scope - my lightweight glassing kit.
The tall is tall enough to use while standing. I'm 6'2", and I also have the center post extension which allows me to look up a hill with binoculars while standing comfortably. Of course, it also works while sitting. I usually will take the tall if I am going to be carrying my 15s and my 85mm angled scope - my heavyweight glassing kit.
Bottom line, the tall is more versatile - it can do everything from sitting to standing regardless of your optic choice. The standard does have merits in real use though.