In the light of no formal safety crash test results, it 'might' be
something German, who normally take safety quite seriously with
performance to match. A BMW M3 convertible 'might' be quite safe if
based on the saloon Euro NCAP ratings, (
though it is important to point out in topless form without the extra
rigidity of the car shell, C pillar airbags, overhead curtains and
other factors, it will perform very differently in crash tests, so
it's only an assumption. There appears to be no independent crash
tests on it or other high performance sports cars particularly in
convertible form as most crash testing focuses on testing mainstream
high volume sales cars. (for greater benefit to the public)
Actually, there are not that many 4 seater convertible cars which can
accelerate to 60mph in around 5 seconds for consideration.
Convertibles are heavier than their closed top counterparts so their
0-60 times are jaded taking them into the 6 seconds territory, e.g.
Mercedes CLK 55 AMG does 6.1 seconds (
) and the majority of sports cars in this convertible category are 2
seaters or 2+2 seaters - the rear only suitable for a small child.
The BMW M3 convertible does 0-60 in around 5.4 seconds
Edmunds.com "Road Test Follow Up: 2002 BMW M3 Convertible" by Karl
The Volvo C70 T5 convertible has 4 seats, a 240 horse power engine,
but 'only' does the 0-60 sprint in a slow 7.5-8.0 seconds.
Another car which 'might' be around the 5 second mark is the Pontiac
Firebird Trans AM convertible, but again there is no safety test data.
What Car? Buyers Guide - What Car? magazine, Haymarket Motoring
I hope that helps, if you need any clarification of the answer just