Thanks everyone for the advice, I think i will probably go down the Unraid route, i havent actually used Seagate drives too much but my current NAS boxes have Western Digital Red drives in them so I suppose I should stick with the tried and tested regardless of the extra few pennies they will cost.

Will definitely be asking you guys for advice once I get the server up and running, however probably looking like it will be done after Xmas due to (hopefully) moving house.

The mrs is letting me keep some money back from the house sale so that I can upgrade my servers so I may end up upgrading the drives in my 2x Gen8 servers and selling off my 8TB N54L