to be honest there are plusses and minusses for both.
I just wish I could afford to run both of them 
I agree completely... 
oh, how in the world can a aircooled be faster than the bis? if you had the older 599cc engine im sure the difference was enormous and even the later 650, and the last 650 el engine (199 something till 2000 ) which was the strongest aircooled had 1 hp less than the BISmarck 
Don't ask me how it is true but on a long uphill the air cooled does better than the BIS did.
The BIS was faster...blimey alot faster! The Air cooled will only be happy at about 60..maybe that is just a confidence thing but the BIS would happily sit at 80mph.
What attracted me to the air cooled was the ability to upgrade stuff which is not available for the BIS which is a pity.
Although the BIS was said to be unreliable, I found mine to be very reliable. But then I had taken the thermostat out and thrown it away. I then filled it with 100% coolant, to hell with what they say about 50% being more effective. I figured I'd rather go 100% so as to make sure there is no corrosion inside the engine.
Part of the problems with BISes I think were previous owners and they were expected to perform like modern vehicles.
I mean a modern vehicle..most people seem to only service the car if it fails the emissions test at MOT!
A BIS needs a little more tlc I think you will agree.
I was at a garage the other day, a young mechanic stared into the engine in amazement. He couldn't comprehend the concept of the engine nor could he work out the layout. I pointed out the spark plugs but because he couldnt see them, I think he still didnt get it. When I mentioned points he looked equally lost!
My first fiat ever and first car was a fiat 500 giardinera. Brilliant little car with an amazingly long sunroof. When you fill it with young 20 year olds you can imagine, bikinis ect were in order

However I was young, impatient, inexperienced, could have done with a self healing car really but my exhaust kept falling off, the sump fell off on one occasion leaving a trail of oil. The fan cowling rattled itself to bits....it had it's issues.
Mainly due to me.
