Use the search function and look for Highpower and cross refrence with my name. You'll get plenty of "how it works" there. The brake is against the rules, and for good reason. It would be fine in an "action" environment where there's only one guy on the line and extreme accuracy isn't a concern. On the firing line in HP, you will be everyone's PITA. If you take off your brake, you'll be running against ATF rules. HP will requre another upper or another rifle entirely (clip sloted bolt gun with iron sights). A Garand is a good starter rifle for HP.
You say you would not be opposed to getting another upper...that is good. Read the Highpower threads and get back to me.
Favor the X.
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