Fog
Grum are you using it with reason still , how does that work out ?
The last track I made had to be 100% Reason due to being a Rack Extension competition entry and so I've only just started on Sonar. Consequently I haven't played with rewiring but as I only stream the main left and right outputs from Reason (rather than individual outs from other channels) I've always been happier than some others who use Sonar's rewire.
I know there is a rewire track I'm working on that would crash X2 if the latency was too low - I suppose I could try that but if that crashes X3 then my good feelings will be sullied

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Bottom line: too early to tell but I can guarantee there will be rewiring in the very near future.
Grum.