Seems fine to me, I'm not sure where they come up with that savings amount but maybe they're comparing to upgrading a regular CP to that level.

Why not just get it at a hobby shop? none around? Mine has a couple, though I bought the last cx recently. It probably won't include a second li-po but they'll be there for help and parts later on. My shop sells them for the same price, sans extra battery and keeps plenty of spare parts in stock. Remember, if you don't buy from your local hobby shop they might just not be there when you need them. Waiting a week or more for a little bity part they'd have had on hand for a dollar instead of a dollar plus $8 shipping is worth a lot.