Experience with double or quadruple pci risers?

[AliasVicturus]

Anyone got experience with double or quadruple pci risers?

I've seen these http://www.ebay.com/itm/1-X-4-Slots-PCIE-1-to-4-PCI-Express-16X-Slot-External-Riser-Card-Adapter-Board-/152664601237?hash=item238b84f295 and http://www.ebay.com/itm/PCIe-4-in-1-PCI-Express-1X-Slots-Card-ITX-to-External-4-PCI-e-Slot-Adapter-Port-/253035242450?hash=item3aea1363d2
Which one do you think is best?

And does someone know how many you can use on one mainboard?
probably depending on supported pci lanes right?

[VRobb]

Possibly, but this: https://bitcointalk.org/index.php?topic=2017600.0

[AliasVicturus]

I did read that.. and that's why i did not post it under hardware.
Wasn't clear for me though were i should post it then