I did it. Click on "Gerald's Truck" in my sig line below and scroll to the second post which details a lot of my early mods including that one... I'm probably the only one here that took the trouble to put a 1", then a 2", then a 3" body lift on.
The hockey puck lift is easy, it does work, and it's very cheap ($10)... but there's a couple of things to consider. Firstly, it's only 1", and I guarantee you that you will not be satisfied with that once you put it on - within a month you'll want to go to at least a 2" body lift. So in effect you'll be wasting a weekend doing something because you will very soon be doing the same thing over again to get more lift.
And hockey pucks deteriorate, so even if you keep the 1" lift, you'll need to replace them every couple of years before they fall apart, so you will once again be committing to re-doing a bodylift on a Saturday every once in awhile to keep it up.
None of that bothered me though since I work on my Explorer all the time, and an extra afternoon every year or two didn't matter.... but what did, was that hockey pucks are made of rubber and every time it rained my Explorer squeaked and squealed like a banshee for the next week until they dried out, lol.
Save enough to forego your next tank of gas and just buy a real bodylift. You'll end up doing it soon anyway even if you put the hockey pucks on at first.