Modern ECUs implement a two-stage rev-limiter, an initial 'soft cut' followed a couple of hundred rpm later by a 'hard cut'. These just cut some or all of the ignition pulses to reduce the revs (or prevent them from rising any higher). On my engine, and also I believe on the 2l Duratec, the soft cut is set at 7000 and the hard at 7200 IIRC.
I would think the GDi rev limit would be around the same, so revving to 7k would be fine, much better to let an engine spin up in lower gears than make it pull a higher gear than it wants to.
