We installed a HKS Hi Power catback exhaust for our client's Evo X. It replaced their Tomei Expreme TI Titanium catback as they had complaints about it being too loud. The install process was interesting as the Hi Power's mufflers were a bit more thick, causing the muffler to constantly be in contact with the tow hook. We ended up removing the tow hook.
Above is the previous Tomei exhaust, below is the HKS Hi Power installed
Removal of tow hook in question.
Below is a clip of the HKS Hi Power catback exhaust at idle and rev.