Its not just only Mongoose and Magnex on the market.

Try Supersprint, reputable maker for exhaust systems for high performance cars from Italy. But I think how it sounds is of personal taste, however I personally think it sound way lot deeper and firmer than single box Mongoose. Down side is they do not do two box oem style version.

https://www.supersprint.com/ww-en/su...worth-2wd.aspx

Hope this information helps.