I am comparing two rackmount server chassis (Norco RPC-4220 and Norco RPC-4020, FWIW), which are identical except for the backplane connectors. One has 20 SATA connectors and the other has 5 Mini SAS (SFF-8087) connectors.
Is there any advantage to having 20 separate SATA connectors? I haven't come across a controller with 20 SATA connectors, so mini SAS breakout cables would be needed (I think) and not to mention all the extra cables to tuck away from the fans. Would an application actually prefer or need individual SATA connectors over the more advanced SFF-8087 connectors?
Does one connection method offer any advantage, such as performance, or is it really just a preference determined by the storage controller choice?
Having the breakout cables allows for better air flow and overall cosmetically better looking. However it limits your RAID card selection, but not by much as most high end cards will have these connections. Having the individual SATA cables you can use the built in SATA connections on the motherboard along with RAID cards as well. This would work great with software RAID applications like md and ZFS. Labeling the SATA cables will be a must with that many connections for install/repair/maintenance.
I personally would steer towards the SAS breakout connections for ease of use. I am not aware of performance issues for either solution.