I have the Olympus 60mm Macro. I like it a lot, though even with the focus limiter it sometimes has trouble locking focus on my GH2. Manual focus is definitely a better option particularly with static subjects but the whole focus-by-wire experience makes me wish Olympus had built this lens with a clutch-focus ring like some of their "PRO" lenses.

If you're going to be doing eye-macros you'll have to get pretty close to your subjects. Most people, even experienced models, seem to get a little uncomfortable when you've got the lens that close to their face and of course you'll need good, bright lighting so that you can stop down the lens and get enough depth of field.

I don't think the Sigma 60mm lens on your list is a Macro. If you're looking for other options, the Voigtlander 42.5mm f0.95 is not a Macro lens but does have a minimum focus distance of ~23 cm and it's quite good as a portrait lens and a low light lens in general. You could also look at the LAOWA 60mm f2.8, it offers focusing from infinity down to 2:1 magnification and by all accounts is a very nice lens - it's available through Personal View Deals but you would need a cheap adapter to use it on m4/3 mount.

@alcomposer What are you going to be doing where it would matter?

I would never have considered the Olympus for film making because of the focus issues. I would look at one of the manual focus alternatives if that is what you're interested in. You're also right, I just tested filming while pulling focus from infinity to the closest position and there is a very substantial "push in".

On the other hand I'm struggling to come up with a scenario for macro-photography where it would matter. If you're focus stacking to get more depth of field while focused close up, usually the plane of focus is moving by such small amount that I wouldn't expect the breathing to be an issue. Macro isn't my main interest, so maybe you have something else in mind or have more exacting standards.

The Leica 45mm doesn't show any appreciable breathing.