Yeah... once you get used to Ableton Live, I'm afraid ANY hardware (unless it's an open keyboard running Live!) is going to be a poor substitute.

And that's kind of the way I feel about it. For fast arranger play captures, an onboard sequencer is OK (just!), but compared to the better software sequencers, loopers, live triggering combo software's like Live, the on board sequencers as full sequencers are horribly crippled. Kind of like writing with quill and ink, just for the antique-ness of it. I always prefer the best MODERN tool for any task, and no on-board even comes CLOSE, IMO...