I am considering offering a large and small size for the grip portion depends on the feed back I get from the first production run, now all shipped.

my glove size is large and the grip works well for me.

Along with a size option, I wonder if perhaps you could include a slot for a grip strap. For an example, see the camdapter plates. I don't think you need a pin like camdapter uses, just a slot to feed the grip strap through.

can't the stock clip be used for a strap, even with the grip fitted?

Mine arrived today. Fits great, and confirmed battery change with grip installed.

Two things for me - improves grip nicely while not adding bulk, and has the camera plate well attatched.

Great grip if you don't want the size/weight of another battery. (thats the part I did not want from the Oly grip - weight and size)

My stock strap is still attatched, and not affected by the new grip.

For the stock strap... I think folks were suggestion a strap loop at the tripod socket area for hand grips.

I got mine yesterday. I'm torn on it a bit. I'm having a harder time getting a comfortable grip I like. But on the flip side, I'm pretty sure no matter what grip, it's still better than no grip.

Personally, I think I'd like to see the grip thinner from left to right (looking at it from the front of the camera). As it stands, it extends over the E-M5 body grip hump thing by a little. I think it should stop there and be flushish with it. At least, in theory..

It's extremely well made btw. I now need something to make use of the built in base =) I REALLY like the fact you can remove the battery. This is a huge gripe of mine w/ the oly grip and why I didn't shell out for it.

Also, other than my previous size comment, it seems like a good balance between the full grip/GH2 style and no grip. It does add a small bit of heft, but I also realized it's a lot easier to grab while hanging from my shoulder. I feel less hesitant when I have to grap the camera strapless as well, a far firmer grip (not that I'd want to do this, but it happens).

yes, exactly, looking for a slot for a handgrip. i really like using handgrips but maybe i'm the exception rather than the rule, so it may not be worth it to add one. the oem grip has a slot for a handgrip but only for the portrait grip section, for the horizontal grip section.

+1 on using hand grips. You are not alone there.
Looking at his photos of the unit , it doesn't look like there may be enough meat there to make a slot that can thread the strap from a grip, at-least without blocking the battery compartment door.. However it does look like plenty of room to have a slot where a tab can be inserted and secured so the grip can be threaded to the tab.

Do you make a version for any other camera?

What is the material from which it is made? It is T6061 and is it Type I or Type II anodized?

A questions for those who have gotten one: Is it harder to reach the shutter release button with this grip attached? The factory grip include a new shutter release button.

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I'm not lazy. I'm energy efficient.

I want to add I used this at an event with my YN560 mounted. Very nice to have it. I did a G3 in this manner and it got painful. E-M5 + this grip made it a whole lot easier (though, still awkward given how top heavy that setup is, but that's for a different thread).

I will also reiterate the love of being able to change the battery w/ the grip on. I'll also add the appreciation of centering the tripod mount on the lens.

I think this will be difficult to evaluate as it's such a subjective matter. I'd say it had no impact in either direction on reaching the shutter. Maybe a little easier even since your hand is less cramped together.