All depends on what you can get the xede for!
The xede isn't all doom & gloom, especially as it's a cheaper option to the tune. the major benefit is you can run 2 maps, 1 for economy & 1 for power/racing. Changeable on the fly! Go over to www.ford
xr6 turbo.com (remove the spaces) & look what GEEA has done with his xede!
I'm thinking of buying one to compliment a tune later down the track.
The sct is the tip of the iceburg, and there's lots better options coming early next year & at a better price. I know one option where u can tune direct from a pc not just some poxy box, others claim to live tune.
The SCT/CAPA edit is not live tuning. it doeshave a l however ot more flexability for changing parameters than a piggyback.