Coke v. Pepsi. which is more accurate?

Things that are crap about my GPS:

1. The thing freezes sometimes when I am uploading. I have to take it apart, and remove the power cell as I am unable to power it off.
2. I have anoying 0 byte files that I am unable to delete without them re-appearing. (I can rename the files, but they are still annoying)
3. no way to plug it into your car battery unless you buy the extras.
4. The software is crap, and I find it much easier to just modify the files using notepad.

Things that might be crap, but I am not sure.

1. Near large bodies of water such as lakes the GPSr will will often tell me that the cache is well off into the lake (often up to 150 meters out there, with a 9m accuracy). This might be a problem with the magellan GPS (the Pepsi), or it might be a problem with the Garmin GPS (The Coke) regardless, one of them has a problem.

I am planning on doing a little experiment with my garmin next time I am by the lake with some aluminum foil. I need to know.. I may have to buy into a backup GPS. Still this is a pretty inexpensive hobby considering these expenses.

So what I want to get, should my aluminum foil plan fail:

1. Garmin Gps
2. Has waypoint Projection ability
3. cheap but not 'cheap' cheap ie. crap

Any suggestions?