Bottom line on front speakers is, what does your brother like? Once you get to the point of good build quality, it comes down to opinion.
If he likes the sound of the MB's (and he is in this price range), he might also like the Boston Acoustics Pro Series, Diamond Audio Hex Series or the Focals'.
When listening to the different speakers use your own CD (this way you can listen to the same track on every speaker, no matter how many stores you have to go to). I like to use female vocalists, for their range. Listen at a moderate level, your ears can get tired.
Power the speakers the way you will in your car...if you are going to use an amp in your car, use one with about the same power on the sound board.
Once he finds something he likes he should buy it, tell him don't worry about other peoples opinions, you know what they say about opinions and a$$holes.