I was going to order MLB EI in lou of my MLB.TV but I saw this when ordering. Im hesitant now, knowing how Dish does their HD programming. This plainly states SD format. It is not worth the price in SD.
EDIT: Id also like to know how they'll handle Astros and Rockies games since they are on Roots and Dish does not carry that channel.
There are lots of teams broadcast on channels that Dish doesn't carry. In addition to the ones you mentioned, a few more that come to mind are the Yankees, Mets, Phillies, and Blue Jays. This also comes up in NBA League Pass and NHL Center Ice.
I've never subscribed to EI, League Pass, or Center Ice (I'm a long time MLB.tv customer), but I have checked them all out during free preview time out of curiosity. I'll use the Yankees as an example to show what typically happens in these situations.
If the Yankees are playing the Tigers, Dish will usually just give Extra Innings customers the Tigers feed since they don't carry YES. Yankees fans are out of luck if they care about watching the Yankees feed because Dish will rarely, if ever, have it.
Now if the Yankees are playing the Mets, Dish doesn't carry either channel. I believe when this happens, Dish is able to get one of those teams' feeds directly from MLB to offer the game to EI customers. You still won't get a choice of which feed you want to watch and the feed you do get will most likely be SD but you would at least get the game.
This is one of the main reasons I have always preferred MLB.tv. With MLB.tv you always get both RSN feeds in HD. It doesn't matter what RSN a team plays on. You will have access to it in HD as long as you are out of market.
Luckily MLB.tv is included in EI so you will be able to get your missing HD feeds as long as you have a compatible streaming device and internet good enough to support it. If you do have both of those things you really need to decide if the Extra Innings portion is worth the extra $55 over MLB.tv standalone. For me it would not be. For other people it definitely is.