quad tip vs dual tip

I got a single exit and it sounds Mean. I dont like the fart can look so i got the STM single exit

I have been running the Ultimate Racing catback exhaust with the straight through mid-pipe option for about a year now. No issues or complains. Fitment is amazing and sound is not quiet but definetly not overly loud. Design and sound is very comparable to the ets v2 exhaust. I ended up going with this one over the ets because it offered the titanium burnt tips, which look amazing, and it was also more affordable than the ets. I recommend either of these two over the ones you mentioned.

I have the cobb quad tip with HFC. I think it is great. It gets rid of the stock exhaust drone. It isn't a loud exhaust, similar to stock at cruise, louder at WOT. I love the look and the sound, but the days of loud cars is behind me. Too may days of running open headers. If loud is what you are looking for cobb may not be the correct choice. If good sound, not super loud and able to make good power then cobb is a good choice. My car is built so I can enjoy it and my wife can drive it without complaining.