I've had several models over the years, and haven't been completely satisfied with any of the digital models I've had and their slow reaction times, but I'm not willing to mortgage the house for one of the really high-quality, high-dollar ones. However, the fun I've had far outweighs any problems. I had no idea how many bucks used my property until I set out the first one, and I've also gotten pictures of practically every kind of wildlife out there. The only large animal I haven't "shot" yet is a bobcat. I know there's a couple here. I don't know if they avoid the camera, or it's just bad luck.
Like Wary Buck said, I haven't found them to be much use in actually hunting a particular deer, but it's sure nice knowing what's out there! I photographed one trophy buck several times in different places over 3 years, and never laid eyes on him in the flesh. Just knowing he was there increased my hunting pleasure immensely.