Received it this evening - will be doing a vid review over the weekend and taking some pics etc. Got a silver/orange and just wanted to give some first impressions.
In terms of quality, it seems very nice. The case itself is two aluminum halves that get a plastic lining into each and then sandwich together over the phone (so yes, the case is 4 pieces). The case is then held together by 6 allen screws - one in each corner, and one in the middle of each long side. Cut outs are in place for the dock connector, speakers, headphone, power button, volume, and silent switches. On the side with the volume cute outs is the e13ctron S4 logo, milled into the metal - it appears that this bit was left raw so it stands out with a nice silver color.
The case itself is actually quite nice looking. I was a bit concerned about the case when I saw the instructions - it's a full page, however it's a full page with pictures and is actually much simpler then it first looked. If I have one complaint about the installation, it's that the heads of the allen screws are very, VERY shallow: the allen wrench doesn't have much room to get in there, so you really need to lay the phone on a flat surface. It's not hard by any means, but I certainly wouldn't see myself taking the case off and on repeatedly - it took about 3 or 4 minutes of fiddling to get the first screw in, the rest went much more easily. It's certainly not as "user friendly" as the alumacase/atomic/element cases when it comes to installation.
The power button, along with the volume and silent switches are all accessible, though I admit having an external button, at least for the power/sleep button, would be nice - the flush feel found on those other aluminum cases is something that I value rather highly since it's a button I use constantly. Again, not a deal breaker, just a thing that would have been nice to have.
The case does give the phone a very solid feel without adding too terribly much to the bulk of it. I would say its a bit slimmer than the alumacase, though it doesn't seem dissimilar in terms of size.
As far as reception goes, and I want to point out this is based STRICTLY on how things looked: speedtest, fieldtest etc have not been used yet...however I did see my bars go from 3 - 4 down to 2 - 3...potentially of more concern, when on wifi my signal dropped a bar from full, even when sitting only a dozen or so feet from my router. As I type this, I've been watching as the phone sat solidly on 1 bar, with only 2 bars of wifi.
I'll do the full write up/vid review this weekend with some actual numbers to quantify what I'm seeing. I'm hopeful that perhaps the numbers will not be as drastic a drop off as the graphical representation seems to indicate. I really do quite fancy the look of the case: the fact that the bottom APPEARS to be thin enough to work with my dock connectors etc is a big plus. I actually even like the way the logo looks...which is quite saying something as someone who generally prefers as logo-less a look as possible. Overall a very nice looking case, well done over all in terms of look and feel.