You can view Dishnetwork as a "manufacturer" and Dishstore as a retailer. The manufacturer will only sell you stuff at MSRP (manufacture's suggested retail price). Retailers like Dishstore can usually cut you a better deal, because they are competing with other retailers.
I don't know which one will have the better price but I'd assume it will be Dishstore.net I give them a huge thumbs up. I've ordered a few things from them and Claude has been great. I also won a reciever off of this site and he got it to me very quickly. I highly reccomend them.
You will get the same products from either, The same people will do the install Claude uses DNSC just like dish does. Claude contributes to supporting Satelliteguys.us DISH Network dosen't. Support Dishstore.