Here's the latest figures, now running a 20Mhz crystal on ICA 7 which is stable at 406.2 MHash with ASIC powered externally with 1.7V @ 3.96A. ICA 6 is the stock reference running at 333MHash.

bfgminer version 3.1.3 - Started: [2013-08-15 20:58:51] - [  0 days 03:00:24]
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5s: 2.66 avg: 3.65 u: 4.37 Gh/s | A:2752 R:30+0(1.1%) HW:92/.82%
ST: 4  GF: 0  NB: 21  AS: 1  RF: 0  E: 9.66  U:15.3/m  BS:36.6k
Block: ...5e0f8f39 #252279  Diff:50.8M (363.7Th/s)  Started: [23:45:10]
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ICA 0:       | 960.4/364.6/422.2Mh/s | A:266 R:4+0(1.5%) HW:10/.88%
ICA 1:       | 543.2/363.7/393.6Mh/s | A:248 R:1+0(.40%) HW:13/1.2%
ICA 2:       | 245.2/364.5/477.8Mh/s | A:301 R:1+0(.33%) HW:10/.85%
ICA 3:       | 423.3/364.2/455.5Mh/s | A:287 R:3+0(1.0%) HW:10/.89%
ICA 4:       | 581.1/364.4/447.6Mh/s | A:282 R:6+0(2.1%) HW:10/.91%
ICA 5:       | 348.0/361.7/441.3Mh/s | A:278 R:1+0(.36%) HW: 9/.84%
ICA 6:       | 394.9/333.8/296.8Mh/s | A:187 R:3+0(1.6%) HW: 7/.85%
ICA 7:       | 294.3/406.2/563.5Mh/s | A:355 R:4+0(1.1%) HW:11/.79%
ICA 8:       | 532.0/363.8/460.3Mh/s | A:290 R:5+0(1.7%) HW: 5/.44%
ICA 9:       | 239.9/365.9/411.1Mh/s | A:259 R:2+0(.77%) HW: 7/.61%
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I've bought a few crystals and heatsinks too many so if anyone wants me to upgrade their units to either 16 or 20 mhz speeds I'd be happy to do it. 

2 day maximum working turnaround and high quality soldering done with an SMD rework station with all components, heatsinks and external power supplies (if necessary) included.  Please PM me if interested.