Come on dude,500km/h and trying a barrel roll for AIM-120 at the same time is suicide :)
My advice is,don't try barrel roll against radar guided missiles.If you really have to,your speed should be 800-1000kmh and you should pull 8-9G's at the same time.You'll likely get blackout,so if he's a AIM-120 spammer as most lobby flyers third one likely going to hit you :).It works really well for IR guided missiles(head on) though.
Umm not really.Afaik it only has a better configuration for cruise missiles(radar etc.)Not an extended booster.So,when it says it has 100-150km range it's l calculated for a slow and low flying cruise missile.Other than that it has the same range with ER for a manuevering fighter.