This isn't going to be a terribly long review and some of you might want to look away now since as many of you know I'm an imager! Therefore, I don't use my eyepieces that much.
The UWAN series
William Optics UWAN series have a 82-deg field of view and come in focal length 4, 7, 16 and 28mm. I personally have the 28mm TANK, along with the 16 and 7mm eyepieces. I will not be comparing these eyepieces to other brands since I don't have a lot of eyepiece, being a self confessed imager...
The UWAN series of eyepiece are all well made and feel very solid and are black anodized. The barrels have a conical shape to keep the eyepiece safely in the focuser, even when using a compression rings. There is a nice rubber ring surrounding the eye that can be rotated to shield your eye from stray light and to provide a comfortable viewing position etc... The lens coating are a deep blue/purple and work very well in controlling reflections. The optical performance is excellent with stars clean and crisp to the edge of the field of view with no noticeable astigmatism precent.
By far my favorite eyepiece is the UWAN 28mm, it really does give a pleasing field of view and high contrast stars across the field of view.
I have only ever seen signs of colour in the eyepiece during daylight and it is restricted to the last 10% of the field of view, to me it presents itself has a golden brown hue...
Are these as good as Televue Nagelers, I don't know, I don't own one to be able to make a comparison.
My favourite eyepiece when actually looking at the night sky.