I've used my TE-17W wide angle 30x eyepiece on my Kowa TSN-883 scope since April 2010 for birding mostly looking at waders at +1000yards from dawn to dusk. The performance in bright light is incredible with bill shape and colour visible at + 1000yards. Even at dusk resolution remains excellent. I only wish magnification was greater and plan to buy the 20-60x TE-10z for this purpose.
Pros: wide field of view & crystal clear image
Cons: insufficient magnification for long distance viewing at +1000 yards
This review was written in the old system and had content requirements that are different than reviews written today.