I take it you get the wobbles only under braking?
In which case, Id take it to the dealers.
Make sure your cars immaculate in and out, so that it looks well-looked after.
If you get no joy, and they try to blame-it on you:
New pads and discs to go-in!
I got a full-set of front pads from Halfords for £24 (halfords own, which are identical to the std renault ones).
Discs arent that expensive... you might as well go for brembos from GSF.