I would be very wary of just looking at it in spread terms. If you get a 3 pip spread in retail amounts that's basically locking in a loss for your broker every time you trade. So you just know they're gonna claw it back somehow.
Work it back through the legs in cable / usdjpy to see what I mean. 6 seems more realistic to me, otherwise I'm guessing you're just gonna get requotes all the time (in which case it isn't truly 3 pips).
GJ