Hello Michelda,
I assume you are not an FAA Test Pilot or anybody who would want to voluntarily overcome the Vmo,Mmo limits the plane has been constructed for, tested and published to operate under, in a daily basis.
If this is so, then you are one of the pilots for which the Airbus Operating Manual is published in order to be followed strictly ( even though we all know the give margin for our screw-ups / Incidents in flight ), this is, the 98% of the flight crew personnel flying their machines.
Being one of these airmen operating under such coditions, I recommend you to adhere to what the limitations chapter has to say about Speed Limitations. along with several other systems limitations such as Flaps, Gear, Tyres, etc.....
Right there you will find a statement, on your behalf, reading :
" SPEEDBRAKES : THERE IS NO LIMITATION "
There´s your limit.
