YMMV Mort. I think I've seen and even used your setup at Katoomba? I believe you'll be cursing at all the new balance issues you will have until you get around it. When looking at low objects I have two 1/2 kilo weights attached with magnets to help keep everything civilized.
I don't have any tracking equipment so watching the objects gently glide across the sky without constantly nudging is most endearing. The more time I can relax at the eyepiece the more immersive it becomes. But, you know all about that stuff.
Even though I am 30 now. I have tested vision of 20/20. I have no problem taking in the view or moving my head around to look around the view.
Regarding your question if you'll be fine? With the ES 100 line you can rest assured that your getting a top quality product that went through proper QC.
RE: The ES 25. Yep hell of an expensive eyepiece but I believe its worth it. A little story to share. I did a test some months back at Wiruna with some of Duncan's eyepieces and the ES Coma corrector to see if I could figure out the correct settings to clean them up.
The eyepieces were the 40mm TMB Paragon, Pentax 40mm XW, Pentax 30mm XW and in spur of the moment 25mm ES 100.
Previously I had tried the ES 25 before I got a CC. I honestly felt it was almost unusable at F5. Noticeable field curvature and lots of coma. I thought it was a novelty eyepiece but nothing to really consider actually buying with my own money. It looked great however in Dunk's C11 HD. But, that's F10. It was impressive in that scope but painful to use in mine.
Anyway, started out with the TMB 40. A nice eyepiece at F10 but appalling at F5. Massive vignetting, staggering amount of coma. Totally unusable. Even using the CC at several settings didn't help it. It flattened the field and corrected some of the coma but no getting around the vignetting. Similar story for the 40XW. It did however respond well to the CC. Cleaned up greatly with some minor field curvature. Still vignetted heavily. Looked superb at F10. I can understand why its a sorted after eyepiece on the used market.The 30XW was pretty poor at F5. Responded very well with the CC. Cleaned up nicely. Very flat and mostly pin point to the edge of its 70 degree AFOV. Was very much enjoying it.
All the time I was comparing it to the ES 82 degree which was used with the CC. The ES CC does a great job on the eyepiece. But, there is minor vignetting on the far edge of that eyepiece when used with the CC.
In the comparison between those 4 I have it to the Pentax 30mm XW. I'm sure anyone reading this who owned a Pentax 30XW would not be surprised by that outcome. Through out this exercise I was regularly switching between the eyepieces to compare and contrast. Probably spent over an hour on it at this point.
Then I remembered Dunk still has that ES 25 100. So decided to give it a go. Didn't bother adjusting any setting on the CC either. Heaviest eyepiece I've ever used. I also didn't have the clairvoyance to bring my counter weights for that trip either. So, anything below 70 degrees in the sky I had to hold the scope up
. The next 15 seconds undid all the work of the previous hour. After coming to focus on the Tarantula nebula and surround star clusters in the LMC I specifically remember yelling in the night across our side of the observing field "
Duncan! I think the ES 25 just won it all!" Duncan described it as if the ES CC and the ES 25 were made for each other. 100 degree AFOV sensibly perfectly corrected from edge to edge. We were astonished. Jason and Ed were there too. I almost threw the Pentax eyepieces back at Duncan and told him to put them back in their case and leave them in there. I believe the 25mm had an TFOV of around 1.6 degrees? It was such an incredibly busy field to look at. Nebula, star clusters, some small globs.
Probably in my top 3 moments in this hobby. The other 2 was last June when we were able to view Saturn in 10/10 seeing for a few hours at Katoomba, and when I first spotted Triton the largest moon of Neptune from my house in Sydney.
I have coveted that eyepiece ever since.
