i feel 2097/XL & W3O always faster than pure in phantom class but this is hard to compare equally : the psX opus with neggie and pure with dpad. Besides don't forget Firmware above 3.0 psp gives a faster feeling on Pure than we had when it launched.

weird stuff :
On the old ones , approximatively ( margin of less than 1 sec) i know where are the limits in term of best time possible on phantom.
About Pure except the 5 easiest tracks i have no clue on what score may be acheivable or not.