My system: U-lock (abus sinus) around chainstays at the rear wheel to pole. Other U-lock, that I will leave locked at school to save commuting weight, locks front wheel to frame. No QR anywhere, no decals on the frame. Here, component theft is practically nonexistent except for the odd qr seatpost+saddle theft. If I buy one of my dream saddles (selle storika, slr xp or flite ti gel), I'll fill up the bolt heads, though.