That's a little hard to answer, because it's not a item where I took both into the field at the same time doing comparisons.
I was using the ID Excel to hunt relics with in fresh plowed fields. The Excel was exceptional at not reporting "hot rocks". No false signals from them at all. The fresh plowed fields produced a lot of hot rocks. The Excel was the only detector I had ever used that would completely ignore them.
A short time after the ID Excel came out, they started developing the ID Edge. I was in on the bottom floor with that one, because Bill Ladd was prototyping a Edge, and I got to play with it. Bill Ladd lives near me. The finished product soon followed, and I grabbed one from stock for my own use, It still had very good rejection of hot rocks, but not quite as good as the Excel. I did feel the depth in disturbed ground was better with the Edge over the Excel. The Edge was also better suited for coin hunting. Shortly afterwards they came out with different coil sizes for the Edge, they never did this for the Excel. I would recommend the ID Edge just because it has available multiple size coils for it. Given the choice, overall usage I would choose the Edge.
Mr. Bill