The '3 Zip' is the type I run with, it allows you to keep the Cockpit open for both driver and passenger, whilst keeping the space above the doors covered - Zero Drafts and doesn't give you that 'enclosed' feeling Side Screens give.
I have only had a 'Fold Flat' screen on one car - a '61 (Beryl the Peril) with the 'Classic' engine; Series 111 or 1V ?. Pre Cortina anyway. That was installed by one of the previous owners. After a previously mentioned incident involving my head and a hard object, I never used it again, nor was I tempted to have another!
