gazcoll:I bought the taylormade R11 iron set to try to improve my game
I got to the the Master tee from amateur within 5 levels of getting the R11 full set.
However, I would probably recommend the full Rapture set instead. The Swing Meter is slower, they are more forgiving and considerably cheaper.
When you get to the Master tee (which isn't very hard to get to) you will lack distance so will probably want to upgrade again so might as well save the credits.