I have 4 20s evo’s, for staying in touch with my wife and 2 daughters when we all go out on bikes, they work well, but you get a Lot of noise when you have a group intercom with 4 people and as stated the range is lucky to make 0.5 miles.. I have had our unit’s for 3 years and not had any problems with them, we all Listen to music and often have the gps giving directions and they will last about 7 hours before the battery gives up. I also ride with ear plugs so have the volume on maximum all the time so I can hear the intercom/music, so that must shorten the battery life a bit. Always seem to have problems trying to pair up individual units (having the intercom to speak to 1 specific person rather than group mode), so now I just hold the bottom button for a few seconds to use group mode, wether I am riding with just one other person or all 3 of them.. have never managed to get the units to go into that mode where you can talk with someone standing next to you (Like at a gas pump)! Many of the features do NOT work,as described in the manual, I think Sena has made a lot of software updates, but have NOT updated the manuals to show those changes.. still quite happy with the units Even after 3 years, definite room for improvement, but they work fairly well, as stated the significant increase in background noise when in group intercom mode is the most annoying thing for me.