Thank you all for your suggestions, all are very helpful
I know that going lower than 3.5mm with such small aperture is perhaps a little over the top. I tried both 5mm Delite and even 3.5mm Delos with my 2x Barlow with manual tracking to get some idea, but I feel, perhaps wrongly, that less glass is better when going for such high magnification with such small aperture.
I have a very good goto equatorial mount that I will ocassionally set up for longer sessions.
Anyway, I made my decision and pulled a trigger on 2.5mm TOE. If this eyepiece will not sit well with me, someone may get a bargain on classifieds in the near future
Thank you all for sharing your experience and for suggestions
