Looking at the Magnaflow Ti exhaust, they "used" to advertise it with a resonator before the main muffler body but clearly, in their pic and their PDF file, there's no resonator. I'm sure that thing is L-O-U-D. I'd ask Jay Laub but I quickly realised he never drives his car, LOL.

 

The Greddy Ti really isn't that loud. Magnaflow has a reputation for not being overly loud and I expect their Ti to be tolerable at least on a twin turbo RX-7. A resonated mid pipe would probably be more streetable with a single turbo. It looks like they come with the tip silencer too but I don't like the idea. The oval muffler JIC Ti would probably be the quietest. Too bad they don't offer the twin outlet tips. I get really annoyed by all the picures showing mid pipes, resonaters, and the wrong tips. Blitz, GReddy, JIC and Tanabe RX-7 exhaust pics on most web sites are wrong and what is showing can't be bought. Frustrating when you see exactly what your looking for but it can't be bought.

The performance of the Magnaflow Ti looks good. It outperformed many name brand exhausts on the dyno on an EVO. Here's the article...

http://www.tprmag.com/issue/5/5_turbo_exhausts.shtml