Thanks for all your thoughts chaps; appreciated.
I do like the idea of the towbar/rear mounted rack combo but is going to set me back around £500 which is by far the most expensive but think provides the best solution (no drag, reduced wind noise, ease of access & removal, leave the roof free to potential roof box, etc). We'll have to see how full my pockets are feeling when the time is right.
Reaching the roof on the QQ+2 is a pain in the arse as I'm 'average' height, I can't reach it easily when washing it (rarely admittedly), so the thought of lifting a bike above my head & onto the roof doesn't excite me. But, for the cost, and the occassional use, shouldn't be ruled out.
I'll think on...
Current -: 370Z GT Roadster / Qashqai+2 Tekna 1.6dci
Gone -: BMW X3 3.0d xdrive M Sport; E46 330i M Sport Coupe; Mazda RX8 231; Nissan 350Z GT Roadster; BMW E90 330d M Sport; BMW E92 335i SE; Maserati 4200; Nissan 350Z; Honda S2000; Astra Coupe Turbo; Ford Probe