Running on treadmill or Stairmaster, which one is better?

I have recently started using the 'Stairmaster' in the 24 hr fitness gym. Before, I always headed off to the treadmill, as I could never get the hang of the elliptical, for some reason I always felt I'd fall off! Anyways, this Stairmaster, a moving set of stairs, is darn good workout. But does it burn more calories than running, for the same time interval? My plan is to verify this experimentally, but I tried looking online too. Also one point to note, is I dont really 'run', more like a jog at an avg speed of 5mph. I found one website called nutristrategy that has some figures to compare. For 1 hour of workout, calories burnt in any activity are listed, I'm copying the ones I'm concerned with :

Activity (for 1 Hour)   130lbs   155lbs   190lbs <-- Different body weights
Running, 5 mph (12 min mile)   472   563   690
Running, stairs, up                       885   1056   1294
Stair-treadmill ergometer         354   422     518

I am not sure which row to look at for the Stairmaster machine, but it cant be the third as that is too less. I could easily burn 285 calories in 30 mins on the machine (and I wasn't doing half as well as the other people around me!) . Well, I guess I will just have to conduct the experiment ( try on both for same amount of time , though not one-after-other as that might affect performance, but on different days) and find out !

MBA or not to MBA ?

Today, I went to Barnes & Noble to seek books which would answer the question haunting me for quite some time now, 'Should I do an MBA?". I found many books ranging from "MBA in a Book" to "How to get into the top B-schools", which tried to answer the question "Why you should do an MBA?" ,"What does a B-school teach?" ,"What kind of a job are you looking at once you do an MBA with a specific specialization?" ,etc etc. But I'd like to know something more specific, like what motivates someone from a technical background to do an MBA.Some of the reasons I could come up with are:
1. To get a job with a better salary
2. To get out of the technical field. Either one is bored with it or just does not like technical work anymore.
3. To move into the Management track of the technical profession itself.
4. You are genuinely interested in managing a business, or being a manager in a big corporation or want to be an entrepreneur.

Points 1 and 4 are not for me. Point 3 is a maybe. So lets discuss point 2.
I am not bored yet with what I do. But I can't imagine myself doing the same work for next ten years or more. Then is MBA the only option?
Having read about what is taught in B-schools and the culture there, I am sure I will enjoy it. It will be a good challenge ,and I'm quite certain I'll make the most of it. But that should be no reason to do it, or can it be?

As you can see, I am quite confused. Next step is going to be ask people who did an MBA, what motivated them to do.. hope they don't reply with the infamous MBA jargon ! :)