Without having compared every item in their catalog, I think iherb is a tad cheaper UNLESS you’re buying a pile of things from your dudes and can combine shipping. I bot 200 qty 5000 U D3 for $10.20 and $2 shipping. Got here in 2-3 days & they ack’ed the order and ship date. This was my first and only order with them, so I don’t have boundless experience with them, but they nailed it.
http://www.iherb.com/Country-Life-Vitamin-D3-5-000-IU-200-Softgels/18038?at=0
We’re talking about nickels, here. Both sources are very competitive. Hey, I know! Let’s get the government involved, shall we?
Cheers!