CD3.5 + Flatcap versus CD5i

A secondhand CD3.5 + Flatcap seems to sell for around the price of a new CD5i. I expect few have heard the 5i, especially in direct comparison with the 3.5 + FC, however what is the general feeling on the pros and cons of each when in use with a 102/180 combination? Aesthetically, I would prefer the 3.5 + FC as it preserves the all-Olive look however I tend to think the performance of the 5i might be superior.