I'm setting up a home Linux-based media server, I was planning on doing a RAID 6 with 8 mechanical drives. I thought I'd pick up a used RAID card for this purpose. I thought the Adaptec ASR-71605 would fit the bill and could be had for less than $200. Researching them a bit I found there's a 71605q model, the 'q' meaning they have a feature where they can also use SSDs for caching (Adaptec calls this MaxCache). However these 'q' models are typically over $1000 on the used market. I doubt I need this MaxCache feature, but out of curiosity, why are these 'q' models so much more expensive? Is MaxCache really worth that much more in the right application?