Roll Bar - off the shelf

[bingo]

Hey all, I am looking for the best options for 4 point roll bars in the United States. I have searched and found a few options like this https://www.thezstore.com/page/TZS/PROD/classic08j15/50-1924

or 

https://www.evasivemotorsports.com/store/product/autopower-street-roll-bar-datsun-z-70-83/

or kits like 

https://www.jegs.com/i/Jegster/550/942703K/10002/-1?gclid=CjwKCAjw1rnqBRAAEiwAr29II-fDTrPgRlqwbrRMi3HRYUqP4_CgwWC0rp-m6XlK1GD3yV2G5EVwMBoCTGgQAvD_BwE

This one looks great, but is in Australia

http://www.agi-precision.com.au/product-category/roll-cages/cams-roll-cages/bolt-in/datsun-bolt-in/datsun-240z/

I was wondering what you all think of your roll bars, has anybody used one of these? I was hoping to tie it to the floor and the shock towers to add a bit of rigidity and worrying that I might need to go custom but thought I would ask before I do. I would like the car to be streetable without a helmet, but would like the added safety for when I am on the track. I would also like as little interference with getting in and out of the car. Any other good options?

[Mark Maras]

 My original roll bar had flanges that bolted to the shock tower tops and another set that bolted to the front of the fender wells. I had to drill those holes. I wish I remember the manufacturer but that was 45 years ago.