Haven't seen anything about the X-Terra 30, only the 50. If they are both Vflex, why does the 30 only use 1 coil (saw this on a dealer's web page), I take it the 30 won't be able to use the smaller coil to change the frequency, is this correct? IF so, for the difference of $170 you'll be better off with the 50. Please correct me if I misunderstood what I saw. Thanks, John