I've had the EDA905, EDB600, EDB400, and the EDC700. I love these Ergodyne basses, the EDC700 was the best sounding of my lot. I haven't had an EDC715 with the triple coil pickup but I believe the 715 is a tad better than the EDC705 (the five string version of the EDC700) if I remember what I've read and only a few of them were made. Same body as the EDC700 series which is very comfortable, neck feels good- overall a very nice bass.
I don't know how much you're buying it for, but a price range of $250-350 would be my estimate. There is one EDC 710 (4 string version of the 715) I know of at GC (gold color) currently selling for $299.99.