this has been discussed many times before. IMO, if you are looking a a scale to give you a moderately accurate reading of your actual bf and a very accurate tracking device of bf gain or loss, than I would recommend the tanita "athlete" scale, that is the more expensive one that remembers your setting, has settings for m/f/c and athlete. There are several caveats:
1. you must weigh yourself consistently first thing in the morning, nude, after taking your morning piss. These scales can fluctate in their readings due to hydration differences. 2. when your hydration goes up, your bf goes down, if you gain five lbs on the weekend of water weight due to carbs and salt, you will weigh more and your bf will go down. 3. if you are sub-10%, they are probably not going to do you much good. I have had a set for five years, keep a daily record and graph my wieght and bf% and have found them to be a very usefull tool for determining if you are gaining or losing fat. They are dead easy to use and do a good job within their limitations. I have used them with a bf5 as low as 8%(briefly!

)Bottom line, buy a set from a place you can return tohem to if you are not happy. Try them for a week and see for yourself.
For most people, submersion weighing is not an option and i think that calipers self-administered at best is a pain in the ass and at worst inaccurate and inconsistent. If you hae a wife/friend/girlfriend that is good at it and do not mind the inconvience, they will do the same kind of job much cheaper.