Everyone I know who has them has the sennheiser unit. It's super clear, much better sound than the rest. The problem with the whole deal is for them to work well you need custom molded ear pieces. You have to go to an audiologist and that gets expensive. Well worth it though. I would order through a pro place like sweetwater. This is not something guitar center knows about. They might give you the best price though after sweetwater gives you the recommendation.
Can't go wrong with the Sennheiser though.
A
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