Both keyboards are great units. You probably couldn't go wrong with either. I bought the Alesis QS8 because the pianos, EP's, drum sounds , etc. were really tops for what I needed to do. I'm using the Classical Instruments Q-card and Sanctuary Q-card. Have a 4 meg flashrom card for storing 50 of my own sequences, have a 512k sram card for storing 8 more banks of programs and 8 more banks of mixes. All-told, I have 1920 programs and 1500 mixes. I can also download my own samples into a 4 meg card or 8 meg card. I absolutely love the QS. Have had zero problems. The only thing I lack is a resonant filter on the QS, but there are so many other bonuses that make up for it. (I've learned to make filter sweeps imitate the resonance). The only other thing I would like on my QS8 is the sequence start button and transposer button, both are on the newer QS6.1 your looking at. Check out http://midiworld.com/quadrasynth/ for more information if you haven't already bought the Korg yet. Hope this helps, PW