Feature-wise, I only recommend staying clear of the SAS controllers due to scaleability. No matter how much someone says "we DEFINITELY only need xyz servers", you can be sure you'll get a "hey mate, I just need two more servers, make it happen quickly thanks". There is no significant feature loss however.
Your answer though is that your most easily supported option is to install a USB or SD card, and boot the servers from that. This in turn can use the SAS array for all its storage needs.