As far as lenses go, the SMC Pentax D FA Macro 100mm 2.8 WR is still a top notch performer. It's sharp from maximum aperture, displays very little fringing, falloff or distortion and it’s built like a tank. It’s equivalent to a 150mm on a 35mm format camera, when mounted on a Pentax DSLR and sports a fast f/2.8 max aperture, life size magnification at closest focusing distance, and weather resistant construction.
Sharpness is already excellent in the centre of the frame and good towards the edges at f/2.8 and stopping down as far as f/5.6 only gets better. Focusing isn't performed internally, so the lens barrel extends by a couple of inches during focusing, although the filter thread doesn’t rotate, making it perfect for use with polarising and graduated filters.
As prior mentioned, the build quality is excellent thanks to the aluminium weather sealed lens barrel and metal lens mount. In fact, you’d be forgiven for mistaking this lens for one of Pentax's premium 'Limited' lenses.
This copy is in excellent mechanical, optical and cosmetic condition, boxed with both caps and hood.
Buy it, shoot it, love it.