Be really careful when removing the limiter, even in sedans they have been know to let go at around 195 and create absolute hell.
There is a thread on FM, showing a tailshaft that let go on the dyno, creating total chaos.
Otherwise though $1200, sounds dear; a uni chip would do it for cheaper, but it might be worth waiting; tuning inprovements for EF/EL EEC-V are not that far away.
FG G6E Turbo- Seduce & Cashmere - Sold
XF S pack Sedan- AU 302 Windsor, T5, 2.77 LSD, Many Mods