Eyepiece::Astromania or Meoptex I am looking into getting a zoom eyepiece for myself, and not sure on what basis to evaluate and compare various options.
For some background on the type of observing I plan to do see my earlier question: Good eyepieces for Saturn and Jupiter
Here are some examples of zoom eyepieces that I've looked at so far

Astromania 1.25&quot; 7-21mm Zoom Eyepiece Apparent field of view is 30- degree at 21mm and 43- degree at 7mm
Meoptex 1.25&quot;-7-21mm Zoom Eyepiece No further information

On these pages there are links to several more options.
It would be a very great help if anyone could help me figure out on what basis I might choose one of these or quickly rule some out, or recommend how I could search for more options.
7-21mm is a pretty common zoom eyepiece option, available from the companies you identified as well as others like SVBONY and Orion. (8-24mm is another popular option).
Doing a quick search for the Meoptex, it appears to have the same apparent FOV's as the Astromania, as well as the same eye relief.  It's not impossible that they are the same design, repackaged for another company.
Another feature to look for in telescope eyepieces is &quot;fully-multi coated&quot; which will minimize reflections and stray light (Astromania, Orion, and SVBONY list this feature, but Meoptex does not).
IN my limited experience with telescopes, it generally holds true that the more expensive options have better performance, but your total performance will be limited by your poorest component.  (A \$200 eyepiece won't make a $25 telescope any better)
You can also look for used eyepieces, advice, and reviews on cloudynights.com.