Ripping 700 CD's to HD using FLAC-How much space?


Hello all,

Currently, I am in the process of transferring my cd's to an external hard drive using FLAC lossless, EAC for transfer and WinAmp for a media player. I would like a HD with enough space for future downloads but am unsure as to what size to purchase? Memory seems reasonably priced these days and 1TB external HD's are plentiful. Also, I may let go of cd's that I no longer listen to after I have them on the HD which leaves me with another dilemma - how many HD's would suffice for backups? Everyone's advice is appreciated. Thanks, Chris

Currently using:
Windows XP Home
Dell XPS 400
Room for 2 internal HD's (using only (1) currently)
chris74
I'd also point out using Firewire or eSata as an interface if you have it. Moving data around is a pain once you have it ripped. Many drives have quad interfaces now (USB2, FW400, FW800, eSata). I'd also use 1TB drives and fill them at most 2/3. Data access speed drops dramatically as the drive gets filled. I have a 1TB drive that is full that crawls even on eSATA. Faster throughput helps for backup, copying etc. And as other have mentioned, drives will fail - so being able copy quickly prior to that event is worthwhile.
many programs will read FLAC so you dont have to convert it. If you need to convert, check out dbpoweramp.....it is an incredible program. You may have to re-load artwork, but all tags should remain.
What's preferable to use, AIFF or FLAC? iPods don't read FLAC do they? Which provides greater levels of compression?
For some reason a backup HD I purchased never worked properly (or I just never set it up properly). As an interim solution and also to keep a copy offsite (to protect against fire, theft, etc), I use Carbonite to backup my music collection. I know nothing about computers and such but if my CDs are ripped in FLAC and I use Carbonite, isn't that the same if not better than using a RAID?