I think the harness are the least worrysome part of the whole accident. The replacement of the steering wheel with a sparco w/o airbag concerns me a lot, esp. with the open face helmets.

What does worry me a little though, is the submarining of the passenger even with the airbag and a 4pt. harness.

An aftermarket 4-pt. is the belt configuration that you have to worry about the most.

Other than the Scroth, I wouldn't use any 4 point. IMHO Scroth are the only company who have one anything other than slap some fastners and buckles on 3" bits of nylon, and actually give a bleep about your safety, submarine issues, etc.

AFIK Schroth is the only DOT approved 4 point harnesses available, not that in itself means much.