Just picked up one of these miners recently. thanks for this post, and the link to the older tutorial for setting up HEX miner using the proxy. I was having a bit of trouble setting it up.
I got some different results than that of the OP when upping voltage. I noticed better hashrate by keeping voltage generally lower (1.200v-1.35v) and clocking the ship to somewhere around 1540-1580 MH/s. My current settings are 1560 MH/s @ 1.350v. This gives me ~22.3 GH/s, and my voltage never tends to top out over 1.220v. It runs a bit on the warm side, but I'd expect it to do so. Running under 1500 MH/s @ 1.200v-1.300v lefter me with a hashrate under 20 GH/s.
Unfortunately, I don't have the tools or knowhow to test heat, and it seems that these do not have a sensor. Although it was advertised at 24+GH/s, that is indeed misleading. You have to run it pretty hot to get 24-25 GH/s, and I'm not sure it's worth it. My current settings leave me with a warm miner, but it's nothing like a couple BFL 10 GH/s units I own that would reach as high as 82C before I began running them without part of the shell, and even had to take one apart to adjust the tension of heatsink, since the way it was put together had warped the PCB, leaving partial gaps between one of the ships and the sink. Now that one never goes above 72C. I don't think this HEX16A2 is getting near that kind of heat.
For the price I gave (at the time equaled ~$150 USD, and I had no cash, only BTC), I think I got a fine deal. Buying gone new for over 220 Euro seems pricey, but if they push them out the door within 48 hrs, and it may be not so bad of a decision. I'm pleased with my little unit, and if I can find a second one for a similar price, I may well ad another and see if I can figure out enough of Linux to run them on a Raspberry PI or something similar.
As for using CGminer, even with the patch, I couldn't get it to work properly. Not sure what I was doing wrong, and I don't have enough skills to get into the nuts and bolts to try to sort out problems myself. After watching the tutorial on how to use HEX miner, that was good enough for me. I think if you mainly have 55 nm tech, you'll be pleased with the lower power consumption this has compared to any BFL units you might be using. Compared with 28 nm products, well, there isn't really any. My KnC Mercury runs at around 143 GH/s, and pulls ~139W from the wall, so less than 1W per GH/s
If you got lower hash rate at 1100/1500, then i suspect that your miner had dead chip
You can check by running ./cgminer-api stats command under cgminer ofc. You need to compile cgminer-api first
[STATS0] =>
(
[STATS] => 0
[ID] => HEXc0
[Enabled] => Y
[Status] => Alive
[Elapsed] => 100391
[MHS 5s] => 20.70G
[MHS av] => 22.23G
[Hardware Errors] => 9220
[Hardware Errors%] => 1.7437
[USB Read Errors] => 66
[USB Write Errors] => 0
[Idled for 60 sec] => 0
[Reset Count] => 0
[Last Share Time] => 1393926290
[Chip Count] => 16
[Frequency] => 1500
[Core Voltage] => 1100
[PIC Voltage Readings] => 1094
[Chip1 Nonces] => 34376
[Chip1 Dupes] => 0
[Chip2 Nonces] => 34412
[Chip2 Dupes] => 0
[Chip3 Nonces] => 34495
[Chip3 Dupes] => 0
[Chip4 Nonces] => 34184
[Chip4 Dupes] => 0
[Chip5 Nonces] => 34719
[Chip5 Dupes] => 0
[Chip6 Nonces] => 34395
[Chip6 Dupes] => 0
[Chip7 Nonces] => 34287
[Chip7 Dupes] => 0
[Chip8 Nonces] => 34318
[Chip8 Dupes] => 0
[Chip9 Nonces] => 34500
[Chip9 Dupes] => 0
[Chip10 Nonces] => 3226
[Chip10 Dupes] => 0
[Chip11 Nonces] => 33925
[Chip11 Dupes] => 0
[Chip12 Nonces] => 34434
[Chip12 Dupes] => 0
[Chip13 Nonces] => 34315
[Chip13 Dupes] => 0
[Chip14 Nonces] => 34609
[Chip14 Dupes] => 0
[Chip15 Nonces] => 34810
[Chip15 Dupes] => 0
[Chip16 Nonces] => 34543
[Chip16 Dupes] => 0
)