racing harnesses

you want a 5 point belt to cover all the bases you asked about. it will stop you from submarineing under heavy braking. a quick release is also a must. The SFI rating is for NHRA or IHRA not for DOT. I don't see why it wouldn't pass though since its more points than the stock belt. Roll bar mount would be the optimum spot for the belt to bolt up but you can use the rear seats lower belt mount as well (wont be able to use the rear seat on that side though)

Most, if not all, SFI rated belts or belts intended for racing, are NOT D.O.T. certified. If you got a real stickler, he could easily give you a hard time and/or not pass your car for inspection. These belts if installed incorrectly could even be more dangerous than factory belts too. I have seen people put these belts in their cars more for show and put them in the wrong way and could potentially increase the chance for injury even in the slightest collision.
As a former Oval Track racer, I used to take a lot of time to make sure my belts were installed at the proper angles to not cause any injury.
I don't mean to come off like a disnick, but this is a sticky subject for me cause I have seen ricers hurt themselves cause they just want to have 5 point belts in their cars
Now, if you want to install them correctly, like having a roll cage or steel bar welded behind your seat and mount them to it, than go for it.They are very, very safe. But if you plan on bolting them to the floorpan or attach to the back seat brackets, than don't do it.

I have heard that it is a STUPID idea to put harnesses in without a roll cage. Ive seen pictures where cars have rolled over and if the people had been wearing harness, that wont let your body roll to the side, they would have been crushed. If youre going to spend the money on the harnesses, at least have a decent roll bar put in as well. Harnesses wont give like a stock seat belt will and in the case of roll over, the stock belt allows you to roll into the passenger compartment, and therefore, not be crushed by the roof of your car. The harness is made not to let you move around.