Fuel pressure regulator only allows changes across the entire rev range.
Once you get your tuner to look at it they may advise uprated injectors depending on your duty cycle or they may use the FPR if its sufficent.(same with piggyback)
You also need a Fuel Cut Defenser to boost past stock fuel cut (between .7 and .9 depending on a number of factors,usally .8)
FPR - 100 max
FCD - 70 max
Emanage blue allows a more fine tune (and is recommended over an fpr+FCD) if you've the money and has the FCD built in plus other features
200 should see it shipped before mapping and fitting.
Also most tuners will prefer if you use a fields extension harness,€120 new iirc
Thats my understanding of it,im sure someone will come in and elaborate a bit better
So it really depends on how much you want to spend and what your spec is.