I use invaders in all my guitars, neck and bridge. They are my favorite. No matter the amp you can get great tone no matter the gain setting. I usually have a high gain setting due to playing hard rock/metal music, but if you roll the volume knob back, you can get all kinds of different gain sounds and still maintain the tone.
Ive never had a problem getting a clean sound out of them. Again the advantage is using your volume knob, even on your clean settings. if you have your tone and volume knob cranked along with your amp, then you will get a mild break up of the signal, but if you practice with you volume knob, you will be able to achieve almost any tone you will be looking for.
It personally gives me alot of options, without having to change all my settings on my amp. example.....I'm playing songs live by crue,ratt,godsmack, then we go into AC/DC and thin lizzy. I simply leave everything alone except turn my volume knob back half way for ac/dc, then thin lizzy roll it back another 1/4 turn. I still keep tone,and harmonics, but clean the sound up so its not so distorted. all this with my amps gain left at about 75%.
I like them because they give me personally alot of options. They will add some gain if you jsut crank them up all the way though.
DID i mention, you need to play with your volume knob?
hope i helped you in your quest, good luck to you.