Tele Vue eyepieces come in several variations and focal lengths to match your particular preferences amongst the variables of size, weight, price, eye relief and apparent field of view. They are universally applauded by both amateur and professional astronomers alike, and hold their resale value incredibly well.
The Radian 3.0mm eyepiece, for many, is the ideal compromise. It has 20mm of eye relief and an apparent field of view of 60°, while not being too heavy or wide to prohibit use in the Tele Vue Bino Vue Stereo Binoclar Viewer. Wide, comfy and relatively light!