Solarflare dual 10Gb SFP+

I saw two Solarflare NICs that are looking really cheap compared to normal:

SF329's:
$75 obo - Solarflare SF329 9021 Dual Port 10GbE PCI E Low Profile | eBay
$99 - Solarflare SF329 9021 Dual Port 10GbE PCI E Adapter 104 | eBay

SFN5162F (only 4.9w but do no support OpenOnload)
$125 obo #1 - Solarflare SFN5162F Dual Port 10GbE Mid Range SFP Performant Server Adapter | eBay
$125 obo #2 - Solarflare SFN5162F Dual Port 10GbE Mid Range SFP Performant Server Adapter | eBay

I saw the CloudFlare case study and sound neat. I don't think these have the new features CF is using.

 

On Ebay now, Solarflare SFN7322F new retail box, dual port 10GbE SFP+, hardware time stamping - only $139 with free delivery:
SFN7322F Solarflare 2 x 10GbE SFP+ FLAREON, TIME STAMPING, PTP SERVER I/O CARD 362312182844 | eBay Ebay item 263945138820
SFN7322F Solarflare Flareon Ultra Dual Port 10GbE SFP+ PTP Server I/O card, ultra-low latency, HARDWARE TIME STAMPING, 1PPS, Stratum 3 clock, 8.0GT/s, PTP daemon (PTPd v2), 0.37 PPM Stratum 3 clock source, MSI-X etc.

PTP Server I/O Adapter with Hardware Time Stamping. Ultra-low latency. NEW IN SEALED FACTORY RETAIL BOX. One opened for photos. Full height bracket is fitted. The low profile bracket is also in the box. Fast and free delivery. Fed Ex next business day delivery is also available.

More details from solarflare.com - very high spec:
Flareon Ultra SFN7322F dual port 10G Ethernet SFP+ server adapter combines accurate host clock synchronization and precise hardware packet time stamping with unmatched message rates and ultra low latency 10G Ethernet.
The SFN7322F delivers unmatched precision and performance on a single data network and in a single PCIe slot for financial services and other enterprise data centers with the industry’s lowest power consumption for additional cost savings.
SFN7322F Highly Accurate Time Synchronization and Precise Hardware Time Stamping Solarflare’s SFN7322F utilizes a highly stable and precise Stratum 3 clock source, which enables a server to be synchronized to a data network clock with greater precision. Standard crystals can drift significantly, resulting in an inferior solution for clock synchronization and time stamping

 

You can pick Solarflare NICs up *really* cheaply if you search for the mis-labeled "Solarflare S6102" parts. Here's one of the SF329 S6102's listed above for $25 shipped: Solarflare Sf329-9021-r7.2 10gb Dual Port Server Adapter Low Profile S6102 | eBay

 

When you say it's "mislabeled", what is the real model number of this card? I'm looking through Solarflare web site and cannot find a match for it. It's currently being offered for $22.99, would it make sense to pay twice as much for Mellanox ConnectX-3 MCX312A-XCBT?