I think a lot of people might find that if they give up a little bit in the max TFOV chase, they would be much happier with the 28mm ES68 or the 27mm Pan than the wider TFOV eyepieces they are using that they find unsatisfactory for various reasons.
The 27 mm Pan and 28 mm ES provide less than 70% of the maximum possible TFoV, for me, that's a lot. Its not a whole lot more that their 1.25 inch 24mm versions. I think 35 mm Panoptic class is a nice balance..
That is very true. What I am suggesting is that some people might be happier with their largest TFOV eyepiece if it was the 28mm ES68 rather than chasing the maximum TFOV options.
As an example here are the main long FL 2" options with my 120mm f/7.5:
31mm Nagler $650, 35.2 oz, 2.83 deg TFOV
35mm Pan $380, 25.6 oz, 2.65 deg TFOV
30mm ES82 $340, 35 oz, 2.73 deg TFOV
34mm ES68 $300, 24 oz, 2.57 deg TFOV
36mm Siebert $229, ~12 oz, 2.88 deg TFOV
35mm Levenhuk $220, 17.3oz, 2.65 deg TFOV
36mm Baader $219, 13.8 oz, 2.88 deg TFOV
35mm Bresser 70 $140, 18.3 oz, 2.72 deg TFOV
38mm Agena SWA $95, 21.3 oz, 2.95 deg TFOV
28mm ES68 $225, 16.0 oz, 2.12 deg TFOV
Optically, the best options might be the 31mm Nagler and the 35mm Pan, but they are expensive and heavy which will knock them out for many people. The 34mm ES68 and 30mm ES82 are also heavy and cost $300+ (and the 34mm ES68 is not nearly as good as the 28mm ES68 optically and ergonomically). The 36mm Siebert is about the same cost as the 28mm ES68 and light, but it is not as good as the 28mm ES68 optically and you might not be able to get one because Harry is so busy. The 36mm Baader about the same cost and weight as the 28mm ES68 but is it as good optically? Probably not as good near the edges from the reports I've read.
The 35mm Bresser and Levenhuk are somewhat unknown quantities. I doubt the 35mm Bresser with 5 elements is as good as the 28mm ES68. The Levenhuk looks to be the same as the Astrotech Titan II ED eyepieces which were a little short on eye relief for their FL and not really much better than lower cost options for edge performance.
Finally there is the 38mm Agena SWA, Orion Q70 - terrible edge performance in many scopes.
So yes - the 28mm ES68 gives up some TFOV, but it costs less than the quality wider TFOV options, is lighter, is comfortable (no blackouts), has good edge performance and no EOFB. And you will get a larger image scale and smaller exit pupil compared to the other options listed above. When you look at all that, there is likely a set of people that might be better off going with the 28mm ES68 than the heavier, more expensive, longer FL options that nearly max out the possible TFOV.
If you can afford the 31mm Nagler or the 35mm Pan and don't mind the weight then great, but if those issues are problematic the 28mm ES68 is probably the next best eyepiece of those listed above. Yet many people might not consider that option because they are thinking in terms of maxing out the TFOV rather than maxing out the quality-TFOV.