diagnosis
OK, sorry for double post, but lots of stuff.
First, here is an album of pictures of the SSD:
http://imgur.com/a/prBe1
some before and after my sanding modification to make it fit. Be really careful when sanding it, if you decide to try this. I would strongly recommend sanding only the connector edge, and not the back of the ssd (the part that actually hits the plastic). I sanded moving the board along its long dimension (side to side, it left a thin line on the sandpaper the thickness of the board, if that helps you picture it more clearly). After very minimal sanding (maybe like 5-10 times back and forth on 100? grit sandpaper) it fits, just barely.
OWC doesn't have much to fix with this drive: just get rid of the v-groove and the break off piece at the connector end, route a tiny bit out of the board like they have on past Air SSDs so it clears the battery plastic a bit more, and while they're respinning the board, why not make the screw hole a plated through hole with a pad to contact the screw (pretty much just like the stock SSD). plated through holes seem more durable, and it's much better to have proper pads for contact, because if you don't, the screw could wear through the soldermask and end up contacting the traces anyway, so why not do it on purpose and make sure no issues will arise if the screw does contact it by making the screw contact it on purpose. Shouldn't take very long to fix this issue at all, but it will cost a little bit to respin the board (though probably not that much).
Second, here is a video of me showing a quick diagnosis of the Envoy:
http://www.youtube.com/watch?v=CV3NX2Iczzo
Also, here is an album of the Envoy diagnosis and fix:
http://imgur.com/a/YU4c8
Basically the Envoy case is terrible designed. The board seems to not be too bad, but I would recommend the same plated through hole changes (to all 3 holes on this) as I did for the SSD. Also, some proper mounting screws for the PCB would be nice, and would ensure this problem doesn't happen again. Maybe even adding a 3rd (and 4th?) mounting hole and standoff (s) would be the safest way to prevent this. Also, the SSD has a screwhole, but they just put a piece of foam in there that presses the SSD against the top case. It seems like the board is touching the foam, but the part of the SSD that's touching the top case isn't the board, it's one of the flash chips. This is unnecessary stress on the chip and those solder joints (and epoxy) that connect it to the board. It really should have a proper standoff for the SSD to screw in to, and it should hold the SSD low enough to not touch the other side of the case. Some more insulation under the board would be smart as well. Lastly, making sure the case is grounded, instead of kinda leaving it floating, would be much better. EMI isn't likely to be an issue, but the case is aluminum, so you have a free faraday cage. Why not use it? (also, the shroud of the USB connector can easily come in to contact with the case, grounding it. better to make it always grounded, than only sometimes grounded. The case of the Air is grounded). Another really minor thing that almost nothing gets right: the LED is really bright. Why not use a translucent plastic instead of clear plastic? Make the plastic milky white, and make the LED white; this fits the Apple aesthetic better. (this is a really minor nitpick, but why not include it while I'm suggesting things?)
Now onto what actually cause the issue, instead of how to fix it: There are 2 bus caps on the bottom of the Envoy PCB, for the 3v3 rail. With how the PCB and the SSD currently mount, those caps touch the bottom of the case. The PCB is at a slight angle, and the side of those caps that touches the case is the 3v3 side, not the ground side. Whoops. All I did to fix mine is to insulate those caps from the case by adding a layer of electrical tape. There still may be excess pressure on those caps, and there still would be rubbing, so that may be a future failure point, even with the insulation. This is why the board mounting solution needs to be changed, and OWC can just add more insulation.
I am in contact with OWC, we will see what they choose to do.
So it's not really a QC issue at all, more of a QA and design issue.