Here is a test of the "XCard" PCIe board I mentioned some months back in the cap card thread, put together by a VideoHelp member called danno78. It's based on an AVerMedia mini-PCIe capture card that does 3D Y/C built into some laptops. According to a member who was pissed off at danno78 for obscuring its origins, it uses the SAA7136 v2.

Snell & Wilcox 4:3 Pattern 1 - three tests

Philips DVP642 - CVBS - Panasonic DMR-E20 - YC - XCard
Philips DVP642 - CVBS - Panasonic DMR-ES15 - YC - XCard
Philips DVP642 - CVBS - XCard

Negative effects of DVD recorder passthrough:

Both have added noise and smear the chroma resolution a little.

The EMR-E20 shifts the image <0.5 pixels to the left, and causes the bottom line to jitter.

The DMR-ES15 mattes off ~2.5 pixels along the right edge. Mine brightens the image, which may be fixable by changing the "Lighter/Darker" setting in the Setup menu, but I can't find a universal remote that will give me that button.

I don't know how they affect the left edge of the image, because my DVD players only output black there.

Comb filter comparison:

The DMR-E20 has a small amount of dot crawl in the 1.0 and 1.5 MHz chroma patches. Other than that, the two Panasonic recorders seem to function equivalently.

They both have a small amount of dot crawl near the top of the image not present with the XCard. Meanwhile, the XCard has additional rainbowing in the center third of the moving zone plate (both horizontally and vertically).

All three require the zone plate to be still for 4 frames to be completely clean. The 3rd frame has slightly less rainbowing with the XCard.

Here is a quick comparison of a shot change on an LD to show checkerboarding: DMR-E20 vs XCard. The XCard has a bit less.

Another card that does 3D comb filtering is the GOTVIEW X5 3D Hybrid PCI-E (the one without "3D" in the name does too, but uses a hardware MPEG-2 encoder). Some PAL testing of that hardware encoder was done by PCtuner.ru, without the SW plate. The ADC is CX23887, also used in the Hauppauge WinTV-HVR-1250 (software) and WinTV-HVR-1800 (hardware). But Hauppauge's comparison table claims that the HVR-1250 doesn't have a 3D comb filter. I guess they forced it into 2D mode...?