Hey,
I'm not on here much so I'll just make one post to what's been posted since my last reply.
I feel fine with the feet that are on the bar as delivered. I did a lot of research on roll-overs of cars with Autopower 4-point roll bars before I decided to get mine. Looking at worst case, convertibles, the floor would generally be displaced a couple inches at the mounting points, but I never read of one breaking through a non-rusted floor (except for here in this thread).
This is a roll bar, as stated, and of course is only designed for roll-over protection. A roll cage is not safe in a street car since there is too much chance of contacting the bars with your head (without a helmet) in an accident. I wouldn't tell someone they're not fast enough to have a roll bar, since an inexperienced driver has just as much chance of going off track as an experienced driver. There are plenty of pictures of proteges that rolled on the highway with very little distortion to the roof, but if I screw up at 120 at Mid-Ohio with my shoulders held in place with a harness, I still want my bar. Yeah, its a pain in the @ss to have a 2-seater family car and I wind up getting comments about it more often than I expected, but I've seen too many videos and pictures of people who made a mistake, caught a rut in the grass and rolled to feel comfortable on track without it. That makes it worth dealing with in my daily driver.
I assumed the original question of this thread was for Solo 1 where a roll bar is required. I agree that it makes no sense to put a roll bar in a car that will never see a track. If you are just autocrossing, there is no need for a bar, and a cage only helps if the chassis you are putting it in is very floppy, which doesn't apply to Proteges.