same time ago i bough a lens on ebay for 40 bucks. the minolta rokkor-x 45mm F2.0 prime lens. its really old lens, manuel focus, but really good optics. with a adapter, i got really high end lens.
the focus peaking helps the find focus fast but for really sharp images you need “MF assist” option of the nex (a digital 14x zoom). the lens itself is plastic and very light, but feels solid.
i am surprise about the good quality of the lens. the old bad things is the MD adapter is little big. the lens without the adapter would a perfect compact size for nex5. but overall a really good lens, not much to complain.
–> i will use it more times.
another one at f2.0
more pictures can be found here