Best in safety
Best in speed
Best in reliability
Best for everyday drive
Best head turner
And best car overall pplease answer each category

too many choices, too many questions.

BMWs of course

My heart tells me to say the BMW, but l am not a fan of the new 1 series. l would take a 335i before the 135i. But of those cars, the Cayman S is very quick, & will turn heads anywhere. l am not sure what ur idea of reliability is, but all the cars u listed r reliable, as long as maintenance is kept up regularly. In terms of safety, l am not sure, but the most important factor in safety is the driver, knowing ur car, & knowing ur limits as a driver, & in different environments. If l were in ur situation, I'd either go for the Z4M, or the Caymen. I've owned two BMWs, with one of them being an M5 (e39), & l hope to get a Porsche in the somewhat near future. The Cayman will be the car l am looking for. l would be using it as a daily driver, & weekend track warrior. The porsche is ur best bet on this list. The Merc & Lexus r too boring. AMG is nice, but with no manual gearbox, it is not an option in my book. The Audi would be the best choice if u live wherever snow is present, as the AWD would be much better off than the RWD sports cars.

Porsche Cayman S, definitely fast and a pretty good head turner.

safety - 135i
speed - tts
reliability - sc430
everyday drive - 135i
head turner - cayman

overall - 135i

z4 only has 2 seats & is so small its scary & is being replaced next year
tts has horrible resale value, overpriced
slk55amg again only 2 seats, & no manual tranny
sc430 is BORING & too big, & been around a long long time, needs to be replaced
cayman is expensive & not as quick as u think

my pick of the best overall wellrounded car in this group would be the BMW =)