the tomei pipes are far bigger than the HKS ones. the HKS outlet it only around 60-65mm the tomei one is 75mm maybe even a touch bigger. the HKS ones are also not finished very nicely inside. the tomei ones are finished very well.
the trust ones are good, but again, not finished all that well inside. plus they are very heavy, and hard to fit, and expensive. I think that is why sewid went tomei this time.