Brdad's suggestion to swap gpsrs is a good way to see how your technique works with an unfamiliar unit. It might also be interesting to see what each gpsr is capable of.
Place all the gpsrs on a picnic table in an open area, turn them on all at once, and see how long they take to acquire a fix, how long they take to zero in on a reading, how close they are to each other.
Perhaps a surveyor could bring a professional unit to accurately determine the location.
Then, go to another table, under some nice pines, next to a cliff, and repeat the test.
We could even video tape both tables and accurately tabulate the results.
I'll bet we could test almost every popular brand in less than an hour.