I use a Optolyth 25X70 draw tube like the CTC .
The glass on the Optolyth, like pretty much like all high end german glass is outstanding
There is simply no comparison on the clarity and resolution compared to the Leupold 15-30 compact
My main range scope is a Zeiss 80mm and the Optolyth holds its own as far as glass
The only downside is the draw tube style is much harder to focus . You get use to yanking it out to find the sweet focus spot . Just not as fast as the Zeiss rapid focus knob
Having said that, the size when collapsed makes it packable in a daypack
The Zeiss 80 is way too freaking huge for that !
If collapsed size is important , then the CTC or Optolyth is the way to go if you can get use to the focus
For range use its not an issue since once focused for your target you are gtg . I have been using my Optolyth more since the size is far more manageable