Ok here is my two cents, I had the x70 and I thought it was the best thing since sliced bread, I was getting deadly with it, I thought no way I could ever get better results with an etrac, but my buddy who is a dealer talked me into an etrac 3 yrs ago....the first day I got it I dug a 8" deep barber dime with a nail in the hole, it literally screamed at me, now keep in mind this area was a small, very small front yard I gridded hard with my xterra, and it never made a peep over this barber, it sang loud and clear with the etrac.
Since getting the etrac 3 yrs ago I have dug 475 silver coins, 379 indians, over 1800 wheaties, lots of large coppers, tons of relics, etc......I absolutely love it. If your using multi tone on your xterra, the learning curve is virtually nothing going to the etrac, if your already in tune with hunting by SOUND and not by nmber it will be even easier.....any questions for me, feel free to ask here or PM me. Get the etrac and you will never look back!