[goodasgold]

Anyone care to share their experiences? I just can't wait!

[VoiceOfReason]

It is sharp wide open and fast. Has some vignetting that can be fixed in post wide open, and stopped down a little it goes away and gets really incredibly sharp. I really like it.

[TaiChiTom]

Congratulations. I love mine. A bit heavy but a great lens. I took it to Paris a few weeks ago. Take a look if you like.
https://www.flickr.com/photos/104373536@N05/sets/72157649180923145/

[MadMathMind]

I've had a marvelous experience with mine. Others have had major problems with autofocus. I've experienced some issues with it but nothing too major; I probably had more with my F50 than this lens. The lens has excellent contrast and color reproduction, although it can be a little cold at times (fixable if you shoot RAW). Bokeh ranges from awesome to rough and is highly dependent on the subject.

I keep this lens on my camera and shoot more than half my photos with it. From a recent trip to Disney World, stats were 52.2% with the Sigma, 8.6% with the FA50, 17.4% with the FA77, and 21.7% with the 70-200 and 71-210 combined. If I'm staying indoors, then I often am over 80% with the Sigma.

You can see results from this lens here:
https://www.flickr.com/photos/127442034@N03/sets/72157649140156878/

I find the lens to be balanced on my K-5 IIs. It's a little heavy to wear around the neck, even for short bursts, so I find myself wrapping the strap around my arm and carrying it that way when I don't just slip it back into the bag. For carrying around all day, it's not troublesome.

[Digitalis]

It is a good lens with a few egregious optical and auto focus bloopers thrown into the mix, it isn't as sharp as the FA31 Limited - even when stopped down. The Lens dock is a good idea, I'd recommend that you get one - as it allows for focus adjustments for different focal lengths rather than one adjustment for every focal length across the lens.

When used in a way that avoids revealing its faults: it is a very good lens, better than most in its focal length class.

I find the lens to be balanced on my K-5 IIs. It's a little heavy to wear around the neck

I never use a neck strap on any of my cameras - and when one is using heavy lenses like this I wouldn't recommended it due to the strains placed on the lens mount.

[brelip]

Optically I give it 9.9/10, but it was too heavy so I sold it, replaced it with Sigma 17-50/2.8, optically almost as good, but definitely slower. I love the internal zoom though.