I totally agree with topic creater. I don't remember exactly how much each (average) episode costs, but its somewhere in the ball park of 150-250 MS points(standard vs. HD). That roughly traslates to 1.57-3.12 PER EPISODE.

Take for example Heroes Season 1. For standard definition, at 160 MS points it translates to $2.00. (or $3.00 for HD). That single season alone is 23 episodes long, so the entire season would cost 46 dollars for Standard Def, and 69 for HD. That means you could go and pick up the show on DVD, for 2 bucks more (http://www.bestbuy.com/site/olspage.jsp?skuId=8385703&st=heroes+season+1&lp=1&type=product&cp=1&id=1645768) and keep it when the new xbox comes out, let your friends borrow it, or ebay it when your done with it. Not to mention you'd be saving a pant load of hard drive space. (at nearly 500MB per episode) Now I work at a blockbuster where we rent out these shows on seperate discs, with roughly 4-5 episodes per disc (depending on the show) for 5.24 after tax(in standard DVD or Blu-RAY for same price). Which means you could buy 2 episodes for the price of renting 4.

If you take in account all of negative factors of purchasing episodes through MP its not worth the 10 cents you'd save per episode.

GRAW's three achievements about getting to the top of the leader boards, each one gets you a mear 10 points and one for some reason get you 8. It's RIDICULOUS! And the 10 nonstop gaming hours in a ranked match. (only counts hours in a game, not just a lobby, and hours were your playing) take well over 10 real hours to get (took my friend 18 hours of straight play)

Surviving 7 days in Dead Rising on survival mode.

GoW 10000 kills.

Beautiful Katamari !00% of collection achievement. (Very Long)

Not to mention the countless ridiculous XLA game achievements.