Code:
Len(TESTSTRING) = 73 
RemoveParentheses: 123.23211 ms
RemoveParentheses2: 125.63364 ms
RemoveBetween1: 416.60941 ms
RemoveBetween2: 237.37265 ms
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Len(TESTSTRING) = 1168 
RemoveParentheses: 1765.64007 ms
RemoveParentheses2: 1654.47126 ms
RemoveBetween1: 1405.39777 ms
RemoveBetween2: 845.45206 ms
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Len(TESTSTRING) = 2336 
RemoveParentheses: 6291.80334 ms
RemoveParentheses2: 6051.99326 ms
RemoveBetween1: 2770.82211 ms
RemoveBetween2: 1730.19534 ms
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