Just stumbled on this thread after a random google search for SR20 injectors...
After tuning hundreds or engines with a huge range of uses/power outputs including SR20de, det, ve and vet I think it is very important to help shed some light on injector options.
Hands down the best injectors on the market are Injector Dynamics and in most cases the
ID1050 sr20 injectors are more than enough for most SR builds and will out perform something like OEM r35 injectors across the board when tuned with a modern ECU such as Motec m1, AEM Infinity or Haltech Elite.
If some one tries to sell you another injectors option i would highly recommend taking a step back and work with a supplier/tuner that understands the importance of running ID injectors.
***If you have a used/free set of R35 injectors or other that are dead set on using SEND THEM OUT FOR SERVICE (cleaning and flow test). You do not want to waste your first tuning session $$$ trouble shooting a dirty set of injectors!