One more thing is I have my internet through Mediacom, so I would have to switch that. Do either of these providers offer internet?
Dish and DirecTV partner up with other providers for internet.
Here's my .02 cents after switching from Mediacom to Dish and Qwest last summer.
On the internet side, Qwest DSL is noticeably slower than Mediacom, but there are far fewer outages. Mediacom internet can be quite good when it's working right, but their email and DNS problems are legendary. At least they have ESPN3, which carries ISU a lot, so that's a bonus for them (I do miss that).
On the TV side Dish's reliability, equipment, and signal quality are far better than Mediacom and at a lower price. We pay about $80/month for 250 channels.
Overall I would say that DirecTV probably has the better national sports packages.
Mediacom's customer service is a nightmare. If you do go with Dish or DirecTV stop by Satellite City in Ankeny (by Palmers), they'll setup everything for you.