I use to have the full set of UO Volcano top Ortho's. And yes i sold them
There outstanding eyepieces. I much prefer the Volcano top ones. Much easier to look into.
From what I have read on CN the HD's have had some problems with the coatings. They have small ER also.
I much prefer people look into a Ortho before they buy. Some people just don't like them. They say yes sharp but they don't like that tunnel view they give.
By the way I have a 25, 18, 12.5 and 6 mm UO ortho's on the way for the little Mak to play with. From Daniel
I have a 10 & 7.5 Parks Plossl which a very sharp.
But with a LX 90 at FL 2030. A 11mm or 8 mm Televue Plossl would be very nice for a small outlay. 11 mm at 185x and 8 mm at 253x. I doubt you will use much more than that. IMO.