I've had one for several years now. Round coil. The thing is great, but I had problems with the ignition module and inductor (I think that's what its called) going bad. It left me sitting at a 4-way stop once. New parts fixed it right up. No regrets.

-Tim
'51 Chevy 3104 w/'56 235, 848 Head, HEI Dizzy, Corvette Cam, Split Manifold and Dual Carter YF's