I have used the bars at one end or the other as it helps move grip to the other end of the car, when I want more rear grip etc. I might add one to the front.
What is the difference between having the same roll bars at each end as opposed to none at each end and under what circumstances would you use them?
Xray T4'16, T4'14 (Wet Car)
Xray X12 2016
wlrc.co.uk (West London Racing Centre)