mass NAS storage options

[raider1v1]

Hey guys,

so heres my plan. rip all my movies, copy all my music, pics, everything onto one massive storage point. i needed that to be linked to a computer so that streaming/ftp can happen. i am planning to use orb for that plus a secure ftp client. needs to be redundant etc. i was thinking of RAID 5 for that. id like for it to be expandable in the easiest possible way.

option 1 - buy the kinda idiot proof Data Robotics Drobo Storage Robot. its just self expanding, healing, all that good stuff. but i dont know if its fast enough for watching movies off of. id start with two or three 500gb seagates for this one

http://www.newegg.com/Product/Produc...82E16822240001

option 2 - get a box such as the NORCO DS-500 5 Bay eSATA RAID Hard Drive Storage Array or the much larger NORCO DS-1220 3U 12-bay Hot-swap Rackmount eSATA RAID Hard Drive Storage Subsystem. I know that this is more setup, and time etc. but its fully configurable my way. id run a raid 5 (suggestions are welcome). my question on this is, do i need to load all the drives i want at once and the array is set or can i start with 3 and then expand out as my needs increase?

heres the link to those 2 above boxes.

http://www.newegg.com/Product/Produc...82E16816133003
http://www.newegg.com/Product/Produc...82E16816133001