I have a FoxPro Prairie Blaster, FireStorm, and SpitFire with an extra SP-55 speaker and Jack-In-Box remote decoy.
All three work out to 100 yards with any problem whatsoever with me sitting on the ground and the unit on the ground too.
Changing sounds, activating remote, is not a problem. I have never tried them out over 100 yards as usually I try to be within 30-40 yards of the caller and decoy, but they do work just fine out to 100 yards.
The SpitFire and FireStorm remotes work great although the print is somewhat small on the FireStorm, still easy enough to read during the day in bright sunlight or at night without any assistance from any other light.
All in all, I give them an excellent endorsement for what I use them for, killing coyotes.