I haven't used any of those, so I won't be of much help. Your best bet in general though is to match a mic with the amp you will be playing to minimize feedback and maximize your amplified tone. Even if other players here post their opinions, it doesn't mean it's the mic for you. It is probably not possible to find any mics designed for harmonica in a local music store, but it is always best to try them first and see how they sound and how quickly they tend to feedback as you increase the volume.
If you buy online, be sure to check out the return policy in case you are not happy. Ideally, I would buy all 3 and return the two you don't like as much.
Sorry I can't be of more direct help, but here's what I use-
http://www.harmonicalessons.com/members/dcforum/DCForumID4/44.html#9
Here's some "avoiding feedback" tips-
http://www.harmonicalessons.com/members/dcforum/DCForumID4/56.html#1
Play on,
Dave Gage
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