okay..first things first, it depends on which part of the world you live in. If you live in a place where it is cold and rains more often then you get sunny days, then go for the berlinetta. The wind noise is noticebly less in the GTB, and you don't run the risk of getting a leak everytime it rains too heavily (my spider roof doesn't leak but i do get worried everytime it pours). I've driven the GTB, GTS and own the spider, and i chose the spider primarily because i like how it looks.
If i had had my practical shoes on, i would've probably gone for the Berlinetta, for the sole reason that it doesn't sound too noisy when i'm flooring the car at 3 times the national speed limit. The GTS on the other hand has the best of both worlds, with a roof which is easy enough to dispatch. If you do decide to get one, choose the one with the colour coded roof, it looks better and you can tell yourself that it's a berlinetta version whenever if you feel the need to.
Now regarding the Spider; the roof is not fully automatic. You have to slightly nudge the roof up a bit, until you hear a beep, and only then will you be able to bring the roof down with the motor. Fortunately bringing the roof up is a lot easier since it comes up all the way by its own, you only have to latch it in place; be wary though, the roof slams itself on the way in, so just put your hands above your head to slowly bring the roof in. I have heard of some faulty roofs for the spider, but i'm sure if you find one with a good owner, it should bring you some great motoring days for years to come.
Regardless of what you may choose, you'll love it, the 355 is a joy to drive, and the sound it makes...?? Nothing even comes close. Get it with the Tubi and you're set, oh and make sure you're a true blue (red?) ferraristi, because the Tubi is LOUD, and if you don't like it loud, then don't get it. But the way it sounds past 5,000 rpms is brutal, almost like a banshee diving it's way through the atmosphere...wailing all the way down. Baritone burble below 3500, but anything above on full throttle will most definately freeze your blood. remember...a ferrari is not just a car, it's an emotive expression of yourself, so choose with your heart as well as your mind and you'll be happy...for a very very very...long time.
