On previous tests I had set GOP in the CBR menu to 3.
With your tip I set it to 1 with all encoder values at 3.0x. On the Pretec card I recorded 29 seconds at 104,813kbps with only about 15% buffer fill, mostly less. A second longer test of 46 seconds was 98,612kbps. Both videos are of leaves in a strong wind.
On the SanDisk I'm getting similar bitrates, but I also had a few Error 70's and the buffer was quickly moving up just before the crashes.
3 log files were created, here's a part of the first one:
Tue Sep 25 15:37:38 2012
37965: 14643.497 [MR] 1 : W=0x4a9b7120, E=0xfa0340, W=0x4a079a50, E=0x536650
37966: 14661.078 [MR] mvrExpStarted
37968: 14663.853 [MR_MOV] AddVideo : (0x4a9b7120,0x81934,0x00000000,0x0,1)
37969: 14663.914 [MR] mvrFrameWrite (Size = 0x81934, Next = 0x4aa38a54)
37970: 14663.956 [MR] mvrEncodeDone (Size = 0x81934, Next = 0x4aa38a54)
37976: 14675.570 [LV] PCLV JPEG SIZE (1056 704)
37977: 14685.342 [MR] mvrEncode (Addr = 0x46000080)
37978: 14685.418 [MR] 1 : W=0x4aa38a54, E=0xf1ea0c, W=0x4a079a50, E=0x536650
37979: 14692.497 [MR] mvrWriteDone2 (Size = 0x102cb0, Next = 0x4a6b2d50)
37981: 14692.650 [MR_MOV] RequestWrite : End(32)
37982: 14692.756 [MR_MOV] RequestWrite : Start(33)
37984: 14692.826 [MR_MOV] WriteSampleData : #1 - Buf=0x4a6b2d50, Size=0x103570
37985: 14702.432 [MR] mvrExpStarted
37987: 14705.981 [MR] mvrFrameWrite : Frame = 72, Pad1 = 8
37988: 14706.056 [MR_MOV] AddVideo : (0x4aa38a54,0x76bec,0x00000000,0x0,1)
37989: 14706.168 [MR] mvrFrameWrite (Size = 0x76be4, Next = 0x4aaaf640)
37990: 14706.212 [MR] mvrEncodeDone (Size = 0x76be4, Next = 0x4aaaf640)
37991: 14706.327 [MR] mvrEncodeDone (Sec = 3, Frame = 72)
37993: 14706.451 [MR] mvrEncodeDone (Pack = 36, 0xb507f0, 0x22949d8 - 0x238cef0)
37994: 14706.478 [MR] mvrGetBufferUsage : Frame=8, Sound=0
38000: 14707.252 [MR] mvrDecideAndAddStorageCBR (0xb507f0)
38004: 14708.728 [LV] PCLV JPEG SIZE (1056 704)
38005: 14710.734 [LV] lvAEResult
38006: 14710.820 [LV] Release FaceAEL and FaceALOLock 9385
38010: 14718.370 [LV] PROP_LV_EMD_DRIVE_RESULT AfState:0
38011: 14726.839 [MR] mvrEncode (Addr = 0x44000080)
38012: 14726.915 [MR] 1 : W=0x4aaaf640, E=0xea7e20, W=0x4a079a50, E=0x639300
38014: 14734.950 [LVFD] LVCPF_SortPrimaryFace( Input Num = 0 )
38015: 14735.064 [LVFD] OutputFace( ID=593, (240, 165), Size=25, Num=0 )
38016: 14744.147 [MR] mvrExpStarted
38018: 14747.800 [MR_MOV] AddVideo : (0x4aaaf640,0x824e8,0x00000000,0x0,1)
38019: 14747.861 [MR] mvrFrameWrite (Size = 0x824e8, Next = 0x4ab31b28)
38020: 14747.905 [MR] mvrEncodeDone (Size = 0x824e8, Next = 0x4ab31b28)
38024: 14752.328 [LVCAE] lvcaeGetAllWbGain(sync)(10)
38025: 14752.633 [LV] ====== lvCompleteALOGetSeed [0x408cd840]
38027: 14753.790 [LVCLR] Out = (0, -1, -1, 0, 0, -1, -1)[0]
38030: 14759.003 [LV] PCLV JPEG SIZE (1056 704)