Geno, I bought an Astro several months ago and it works flawlessly even in heavy cover. My brittany, Jake, will hunt out over a 1/4 mile at times and it tracks him well. Also the features of the gps unit itself are wonderful. The only problem I have had was holding a shotgun in one hand, playing with the gps with the other while walking into a group of sharptails that the dogs had pointed. I was so caught up in the gps I didn't see the dogs until the birds got up. I have never tried it to it's maximum range. Peter
