I have a garmin 60cs and I went caching a couple of weeks ago with a friend who has a magellan, sportrak I think. We found 4 caches, 2 each. The only difference we could see between the 2 units was that he walked right past the caches and had to come back. Not by much only 20 ft or so but we would get zero readings at very different spots. It worked out well because we then walked toward each other and usually the cache was right between us. It was a very enjoyable experience having a different brand of GPSr in use, my usual caching partner uses my ols etrex and we end up close to each other but not to the cache. It seemed to us like the garmins and magellans just have opposite zero readings that happen to work well together.
Other than the slight boomarang problem, and it wasn't really a problem, I think magellans are fine units. I do like the way my 60cs fits in my hand though, as well as it comes with a clip to hook it to the sternum strap on my backpack.