I'm a fan of the Burpee coir pellets. They are a lot easier to deal with than peat pellets (e.g. Jiffy), and peppers do seem to like them better - it could be a pH thing, not sure, but pepper seedlings do grow better in coir than in peat. The coir also does not quite harden like a brick if they get dry, as the peat pellets do.
It's just a growing/starting medium; there is no nutritional value. I give my seedlings a squirt of weak fertilizer after the 1st true leaves are up.