I subscribed to this a couple of years ago, and was unable to get quality audio streams, let alone video, even on a 5mb connection. Not only that, but they blacked out local-market games - heaven forbid a fan actually wants to follow his regional teams. About the only good thing I can say about MLB.tv is that they refunded my money fairly quickly with no questions asked.
I subscribed to this before the "premium" service (HD) was not included and then DVR features didn't exist. Had it last year as well but last year was again terrible. Literally every game I wanted to watch was blacked out and the audio and video quality was not that great (on a 30Mbps up - 2 down). Have not purchased it this year and don't plan to - is not worth it.
I have subscribed to this since it started. I RARELY have a problem. Good internet connection is a must.
Many above complain about blackouts, this program is for OUT OF MARKET games. Watch the game on regular cable, TV if broadcast, or there are other ways to stream through the internet that you can find.
If you live out of your favorite teams market, like I do, or even just want to watch more than just your home market team, this is well worth the money. $120/year is affordable for a true baseball fan.