Observing with the UO Super Erfles

Good Day All,
How are your gut feelings on observing with these eyepieces? Although having a full set of UO Orthos, I am curious if the Super Erfles would be a step up as far as greater FOV and sharpness(1 additional lens). Oh yes, the scope used with these eyepieces would be a 12.5" F/5. Eye relief is not an issue as I like to snuggle my eye with the front lens.

I had the 20mm Super Erfle. I liked it at f/8. It was a "nice" eyepiece. Inoffensive, if you will. Good for general purpose low-to-medium viewing. It did show mild softness at the edges, although the central 50 degrees or so were pretty darn good. However, at f/5 I suspect the edge performance would start to get pretty ugly.