My M42 to M4/3 adapter just showed up and I'm not excited about any of the M42 lenses I've acquired. -Tamron 28mm f2.8: Image quality seems pleasing, but the focus ring sticks a little. Aperture ring is a pleasure. -Sigma 28-80mm f3.5 zoom: control rings feel cheap and cumbersome to use. Seems reasonably sharp and not a lot of glow wide open. -Panagor 85-205mm f3.8 zoon: with the long flanged adapter, this thing is a monster to handle. But the image quality has potential to be better than my Hexanon 80-200 f4. But the Hexanon is so much easier to handle. I left the SMC 50/1.8 at my parent's place on the Pentax body because I preferred the Hexanon 50/1.8. I don't regret that. What other M42 lenses should I consider acquiring?