First of all, don't buy one yet. Remember; we still got the drawing coming at the end pf the month, which will get you BOTH, as well as the "Name a knife company" thread, which will get you the knife of your choice.
In answer to your question, I'd go with the Magna. The clip is detachable, and the pins are accessible to the consumer; you'll notice that this is not the case with the impulse. Personally, I don't like the idea of a recessed clip. It'll either tug at your clothing or bend the clip. Of course, this is just my assumption. Feel free to prove me wrong, and I hope you enjoy whichever you buy!