These are macro shots from my OM-mount 100mm Vivitar mounted on an E-PL1. It was originally shipped with a matched diopter which gives 1:1. Got it off eBay several years back for $90 for use with my OM-2N. Using it on the E-PL! has been incredible. The magnified view for MF is sooo much easier than the OM-2N viewfinder. It will be even better with an EVF. m43 is such a flexible and affordable system!
Your thread prompted me to drag out the lens and fiddle again. Drab rainy day here so a good chance to experiment with manual focus again with my E-PL1 on near and distant scenery under poor light.
Using the E-PL1 LCD is rather hit and miss, as default it's hard to judge the focus point, at 7x magnification it's easier but the user wobbles make for headaches.
Plonk the VF-2 on and suddenly it all does make sense, it's way easier to judge focus at default size with its 800x600 pixel display, no need to go to the sea-sick inducing 7x magnification.
At f/3.5 the focus point is quite critical even at about 50 feet, f/8 (its best aperture) is a bit easier.
This time with the E-PL1 I'm not seeing such a difference between F/3.5 and F/8, quite unlike using film where the difference was obvious.
The good thing is the VF-2 display stays the same effective brightness whether the aperture ring is at f/3.5 or f/22 (and Live View Boost is off).
That is quite unlike an optical viewfinder where at f/22 you can't see to focus. Maybe that's why I didn't use the 100mm Cosina because I used to try and use it on my E-300 and its tragic viewfinder made life very difficult indeed.
So thanks indeed for getting me to explore my old film lenses again, I might soon become a true Peter Nelson disciple....

or even a Tedolph disciple for that matter :-(
And a final thought, the E-M5 with viewfinder and ability to stabilise at half-press will make life so much easier for non M4/3 lens users, it should cause another surge in use of those old film lenses, buy up before they all disappear.
Regards....... Guy