Going to buy a couple of R2312GZ4GCSAS 2U servers and I believe they have the RMS25CB080 HW RAID controllers in them. My question was more for a battery backup for the write caching and Intel list two options: AXXRSBBU9 or AXXRMFBU2. The SBBU9 seems like a more traditional battery and MFBU2 seems to be some sort of solid state memory option. My question is what one to go with for reliability of write caching? My mind says the MFBU2 seems like a nice tech move in the correct direction but the battery is tried and true. Any thoughts?