Starkeeper,
  Sadly neither the PSR-540 or 550 will loop user pads...  I'm not sure how they were set on the 640 and 740.  Using multipads doesn't make anyone a wimp.. It takes a wimp to make a statement like that because that person doesn't realize the potential for them.  I do know that you can loop them on both the 1000 and 2000...
Squeak
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GEAR:  Yamaha MOXF-6, Casio MZX-500, Roland Juno-Di, M-Audio Venom, Roland RS-70, Yamaha PSR S700, M-Audio Axiom Pro-61 (Midi Controller).  SOFTWARE:  Mixcraft-7, PowerTracks Pro Audio 2013, Beat Thang Virtual, Dimension Le.