In fact, there is no so called the best players. If you have only 3 players, or serious comparing to limited players, you can say some specify player is the best among XXXXXs.
To my experience, HIFIMAN, T51, Zune, Sony X, iphone 3G , Cowon D 2 are the same league, it is hard to tell which one is the best. if you must say which one of them is best, you can really say one depend on the specification sheets. But it is unfair to make such a judgement. T51 has 5 cores ( including two DAC chips), but the price of it is only 1/5 of hifiman which has only one DAC chip. Don't get my wrong, I am not saying T51 is the best one, it have no any essential difference with the cheap Sansa Clip in term of sound quality.
Even Sansa clip can be the best one among any DAPs.( best DAP in 2009 on ABI website).