Facts:
-Targas are less rigid than coupes
-Targas have interrupted body lines compared to coupes
-Targas are more prone to leaks than coupes
-Targas have more air drag than coupes
Despite the above facts, nothing beats the open road with the targa top off on a nice day. You can hear the sound of the engine better and I like the open roof without too much air flow in the cabin like in a true convertible.
Personally, I rather just own both a targa and a coupe. A targa for most driving and a coupe for the track and pictures.