I have run both coils AND 1/4 elliptic springs.  The 1/4 elliptic springs work MUCH better.  Less body roll, more droop and more compression.  I attribute this to the 1/4 elliptic springs being progressive and the coils I run are not.  The only problem I have seen with 1/4 elliptic springs is the main leaf breaking.  The main leaf sees allot of stress compared to regular full leafs.  If you break a main leaf on a 1/4 elliptic pack you are getting home on your bump stops.

Leni