With all aspects of life concerning numbering...there always has to be a person on the bottom of the list and on top of the list. For example, competitive weightlifting there has to be someone who only squats 400 pounds and gets last place. Likewise there is a muscleman who puts up 800+ receiving first place. The question is: where is the respective cut-off?
Translation: There can be someone who plays a Hungarian Rhapsodie the slowest (instead of Presto...it is Allegro) and there is someone (like Cziffra...just a side note for clarification--I do not find his H.R to be the greatest in the world, however he is one of the top 5 for Liszt's other works e.g. Grand Galop Chromatique
) who just goes overkill sometimes (most of the time) and plays it really fast.
Generally those who set their tempo in the middle of the pack or play at the high end are regarded to be playing the piece better, whereas people who play the piece slow(er) are not considered so great.
My advice: See if you can match the Mazurka King...Rubinstein...if you cant play as fast then slow it down, maybe 10bpm (depending on the piece) to be in the average range.
....I hope I did not stir up any controversy