I'd rather have this than nothing at all. Don't hate it if you haven't had one yourself. A lot of "nay say" on these forums is such bulls***.
OK. Here's the thing man. EVERYONE on the forums lately has had sand shoved so far up their vaginas that in 5 years they're going to be pissing glass. Everyone needs to chill for ****'s sake.
You've had your Miata for a few months, Dub's had his a bit longer, I've had mine for almost 2 years, and Muff's going on... well... much more. Everyone jumps to a pissy conclusion and usually says something about hating. Can we ditch the petty bulls*** all around by everyone please?
Style bars are simply that. For style. They mount in two points and do dick for handling. They are mounted in the stiffest part of the car. Not to mention they're not connected to any suspension component. I question the logic behind the handling issue. Side impact... ok, it could help a little bit if hit between the door and the wheel well. If you get hit directly in the door, it's not going to help. Another questionable point.
Full roll bars mount in 4 or more places, adding more rigidity to the chassis. Will that help handling? Maybe a little. A normal person may never notice. Will it help safety? In the event of a roll over, sure. The link I posted shows a lot of roll over cars. I never know what may happen in my life, but I'm damn sure going to make sure that I have something protecting my noggin in the unlikely event of an accident.
So what you choose to do is obviously your choice, but please take these ideas as thoughts. I know you scored it free. I know they sometimes look pretty good. But let's not get too ahead of ourselves with questionable information.