little info.
I aided a friend last year (9 months ago) in buying
the M-Audio Axiom 61, and overall, it seemed like an okay piece of equipment. My background is to always buy the best quality gear (for myself), but this girl I helped had a budget.
Also important is what software are you planning to use? She got set up on Reason 4.0. Last year,
Propellerhead Reason 4.0 did not have the latest driver for working with the Axiom, nor did M-Audio have a driver that took advantage of all the latest features in Reason. But, I did find a patch that enabled the Axiom to do all that the new Reason 4.0 does.
My personal gripe with the Axiom was its keys. I thought them on the cheap side. Which would cause me to take "Talontsiawd's" word (above) with serious consideration. He said the Akai's keys feel even worse than the M-Audio Axiom.
I have not touched the Akai gear so I do not know what to say of it. If the price is $150 more, you would expect, as a consumer, that the equipment should be better constructed.
Lastly, I just googled
the Akai MPK 49 and watched a Youtube video from a guy who has posted several videos on it. He seems to be quite knowledgable about it now, after having spent close to 40 hours of research and trial & error, trying to get the Akai to do all the things it is supposed to do. He loves his, but said its setup / initialization with your software, can be a headache. His videos tell how to overcome what he spent hours learning.
https://www.youtube.com/watch?v=aPC8vb7Z9wE
Hope this helps.