I have a Foreplay II/C4S and a Quickie/PJCCS. Both are similarly modded with PIO caps. They both have their virtues. But I tend to listen more to the 4Play for better dynamics and drive for my Paramours. To me, much depends on the downstream components. If your amp's input sensitivity is pretty high, you may not need the extra gain and drive from the 4Play. But, quite honestly, $100 for as much fun as the Quicky provides is well worth it!!
Cheers,
Geary