i think a cage is a very good idea, and i am in the design stages of doing my own cage now... just got my bender last weekend 
so the reasons its a good idea are obviously all safety related...
first off, you are driving a tiny civic... and if you would like that dodge ram thats gonna t bone you to not destroy your skull, then a roll cage is a good idea... also if you like doing 80+ mph, and believe that ANYTHING can happen and no matter what you do you are not a perfect driver, then a rool cage is a good idea...
with the percentages of suv's/big ass trucks on the road today, i think its a safe bet that a roll cage will help you in the event of an accident with one of these horriblely huge gas guzzling civic crushing trucks...
so the reasons its a good idea are obviously all safety related...
first off, you are driving a tiny civic... and if you would like that dodge ram thats gonna t bone you to not destroy your skull, then a roll cage is a good idea... also if you like doing 80+ mph, and believe that ANYTHING can happen and no matter what you do you are not a perfect driver, then a rool cage is a good idea...
with the percentages of suv's/big ass trucks on the road today, i think its a safe bet that a roll cage will help you in the event of an accident with one of these horriblely huge gas guzzling civic crushing trucks...