walt,
I have six 550's. Just received the last two a few days ago. As of yesterday, the original 4 have been out filming for a little over a month and a half. All on high traffic runways, all capturing on the everage of 12-15 20 second videos/day. All the cams are on their original set of batteries, all have at least half their battery life left.
I have two 2GB SD Cards for each cam. Every 4 days or so I make my rounds and swap out cards. The whole process takes about 10 seconds/camera.
I can speak to the camera's video capability only, since I have yet to take a single still picture with them (3-5MP). Personally,I think you run the risk of missing a lot snapping a single picture. With the resolution set at 640x280, I can get 240 15sec videos on a 2GB sd card. The camera's 1.2 second trigger time is good for walking targets...a little slow for faster ones (if the cam is set perpendicular to the trail. Turning the camera so that it faces the trail at an angle fixes that problem. The vids are sharp and clear, both daylight and night time IR images. Sensitivity is great. I've had many triggers caused by deer 25 yards+ from the camera....and that's with the sensitivity set at Medium. Frame rate is good at 16FPS with resolution at 640x280.
The camera is about the size of a beer can. Rediculously small. It straps to the tree with a friction-type buckle and strap. The strap IMO is too short, but that is easily fixed.
Awesome camera....buy one....or six /forum/images/%%GRAEMLIN_URL%%/smile.gif