A) This 6mm is likely just a rebrand of the TMB Planetary Line as same elements and ER (7 elements / 4 groups) -
https://www.ozscopes.com.au/skywatch...-eyepiece.html
B) This 6.5mm is likely just a rebrand of the Celestron X-Cel LX line as same elements and ER (6 elements) -
https://www.ozscopes.com.au/saxon-ci...-eyepiece.html
C) This 5mm is likely a rebrand of the Baader Hyperion as same elements and ER (8 elements) -
https://www.opticscentral.com.au/sax...l#.XAYFv2NRepo
I've owned all three under their primary branding (TMB, Celestron, Baader) and used in scopes from f/4.7 Dob to f/8 Apos. I liked C the best because very comfortable 20mm ER with big eye lens and 68 degree AFOV. Not sure on this branding but the Baader branding can add "fine tuning rings" that lengthen the eyepiece and change the focal length. Do not see that on the Saxon site so these probably stay fixed. But it was fun as they had 3 different ring sizes so could get a lot of different focal lengths from one eyepiece with those very inexpensive rings. After C I liked B next best, then A. The A Celestron X-Cel LX worked fine but off axis was not as good as others in fast scopes and had some edge of field brightening. All three come in at $150 or less in AU.