I have a 2001 non turbo sports special Impreza, and I was wondering if it's worth doing a de cat as previous owner has done a right bodge job on it....pipe welded straight into first cat, and it's ruined the power and sounds like it's constantly blowing...not to mention they drilled the air box...!! I looked into cats again but tbf they are just stupid money, any help appreciated and where is best to buy from. Thanks in advance