I think you mean the 12x13 inch Nel tornado coil. It is a great coil, so far heard nothing but good reports on it..
I have been hunting with 15 inch coils for over 8 years now, have 2 excals, one has the original WOT on it and the other has the original Detech 15" SEF coil on it and I have had no problems hunting in the surf or pinpointing with either one. I could never go back to a 10 inch coil, they are too small for me, not enough depth or coverage on the beaches I hunt.
You learn to sweep the coil with the ebb and flow of the current and not fight the current. I side step with the surf as it rolls to shore and then side step back as it recedes from the shore letting the current work my sweeps. I usually hunt a 10 foot wide path doing this. Point point is easy, once target is located you place your toe of your foot at the back of the coil, remove coil and start your scoop at toe of your foot before moving your foot...
I am getting ready to buy another excal to customize for travel, I am going to have a 3 or 4 piece travel shaft custom built and I will be installing the same 12x13" NEL Tornado on it that you have as well as do the remote pinpoint mod on it and add Grey Ghost Amphibian headphones just like my other 2 excals have......