I'm looking for the benefit of years of experience and contacts to summarize for me the lowdown on roll cages. I'm in my first season of sprints with my stripped out, but still road legal (I hope), Pace/Koni suspended, R type tyred, lowish budget 75 V6. After seeing the great coverage of the East Coast Challenge, the rolled Sud at Pukekoe and a rolled Mini at Bathurst, I have become more interested in participating in a broader range of events and improving the strength of the car . Having taken the headlining out, it is now blatantly obvious that the main function of the roof is to keep the rain out, rather than form a solid protective structure.
Since there is no one on the sponsors page in this field, hopefully people can make recommendations on preferred suppliers. The more I looked at websites and CAMS material, the more confused I got. My questions include:
1) Is a half cage an option or are they only acceptable for those that already have them?
2) Is there an accepted appropriate design for our level of motorsport?
3) What are the pros and cons around weld in and bolt in cages?
4) Are cars road legal with cages in Victoria?
5) Would the recommended design change if during the remaining life of the car it may end up with a 164 or 24 valve V6 in it?
6) Who offers a good reputation and balance of product and price?
7) What budget expectation should I be thinking of?

What weight penalty do you have to accept?
Please offer your contributions to any of the questions you have an opinion on. I tried a search on the forum without success, so don't think this has been covered recently.
Thanks,
John