Thanks guys.
Nillerbabs, I'd say the LP is less complex, in operation and in sound. But in addition to that, I think the LP has a unique tonal quality, although it's hard to put my finger on or describe it properly. They certainly sound different - even purposefully attempting to make them sound the same is difficult. I haven't done any scientific-style comparisons as yet; suffice it to say that they are both identifiable within the same mix (that's evident in that clip I've posted here).
Personally I've found myself relegating the LP to "gritty," "fat," "raw" duty (often bass lines, like in my vid), while the Voyager automatically gets anything that needs prettiness or nuance. This is personal, but I'd rather play jazz licks on the Voyager. However that's not to say one can't do the other. And do be honest I'm still not fully in control of the Voyager - it's a complex instrument.
Also don't forget the LP has a couple of features not present on the Voyager; particularly "overload" (which can create a massively fat sound) and arpeggiator (on the Stage II and subsequent). Also, I reckon the LP build quality is second to none... I've had no probs with the buttons or keyboard, and the chassis is tank-like.
Both instruments are superb and I'd not trade a body part for either - both of them cut through a mix like other instruments can only dream about

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