Just an FYI. I tried putting two 9361-8i cards into an HP Z820 and could not get it to boot past the MegaRAID configuration. The drives for the first card come up but when it gets to the second card I get an error:
Host Adapter - Bus 8 Dev 0:
F/W is in Fault State - MFI Register State 0xFFFFFFFF
F/W has indicated system reset is required. System will reboot now.
Above it is the drive virtual drive list, the actual hard drive list and the Bus 7 Dev 0 info for the first LSI MegaRAID 9361-8i. If I remove the second card then I boot up just fine. Tried all the ports for the card that I could and even disabled the onboard LSI-2308 to no avail. I imagine it is an IRQ error but I don't know how to switch the IRQ in the BIOS (legacy).
So it looks like you can only have one 9361-8i card per box. Interestingly enough I had a 9270-8i and threw that sucker in the box and it does boot successfully (after three restarts to let the box configure itself). So you can have a 9270-8i and a 9361-8i living together, just not two 9361-8i's in this instance.
I looked into the compatibility doc for the 9361-8i for an expander/backplane http://www.lsi.com/downloads/Public/RAID%20Controllers/RAID%20Controllers%20Common%20Files/MegaRAID_SAS3_936x-938x_Compatibility_List.pdf
It lists one 12Gb/s backplane: Supermicro BPN-SAS3-216EL2 which came in around $1k http://www.wiredzone.com/Supermicro-BPN-SAS3-216EL2-SAS3-12Gb-s-dual-expander-backplane~10023383~0.htm
Anyway I have 4x Samsung 840 Pro 256GB in a RAID10 for boot drives, and 4x 1TB EVO in RAID 10 for data attached to the 9361-8i. Waiting for 12Gb/s drives to drop in price.
FOR SALE: one 9270-8i w/BBU and mounting card, one 9361-8i w/CacheVault BBU. Make me an offer on your preferred card if interested as I have no need for them now. Both are brand new with less than 20 minutes runtime on the 9270-8i and two weeks of runtime on the 9361-8i (wouldn't operate reliabily in a Dell T620 purchased in December 2013).