I have a NetApp FAS 2040 version 7.3.3 filled with Twelve 3.5 Inche drives at 15K and 600GB. I need another shelf with more disks as i'm running out of space. I really don't need all the IOPS. Our NetApp sales guy and NetApp support are telling me to go with 15K drives on the new shelf which is the DS4243 as shown.
Which of the two models do you think i should go with from the link below (DS2246 or DS4243) and why?