Better for what ? That's way to broad of a question to answer. I have never seen any one detector that was overall better than others. Under certain conditions there is always a couple that do better than others.
Between the ID Excel & the ID Edge I would suggest going in the direction of the ID Edge. It offers the user a few options the ID Excel does not. The main one would be the availability of optional coil sizes. They are no coil options for the ID Excel. The ID Edge does have a different circuit, and software running it.
I have found that the ID Excel handles the hot rock problem better than the ID Edge, not that the ID Edge doesn't handle the rocks, in fact it does real good at it. It's just the ID Excel does exceptionally with it. Now this is the hot rocks in my area, (New England).
I somewhat feel the ID Excel does better hunting in the trashy areas This is of course if they both use the stock 8" coil. This was tough to answer, because it's been a long time since I hunted with a ID Excel. I switched to the ID Edge when it came out, and with the 5" coil available for the ID Edge, it's a super trash area hunter.
One can purchase a ID Excel for less cash than the ID Edge, so if the price is right & your going to use the unit for general hunting, The ID Excel is a good deal. You may still be able to locate a new one with a lifetime warranty from a dealer the has new old stock on hand.
Sorry if I sounded contradictory, but it's a tough choice.