Scwarzkopf Blonde Me...discuss

Heard good things, about how it gets the stubborn out but doesn't damage...now idk. I quit BB because I was feeling damage but I never got stains out or past yellow and I did want pastel. But if it's not possible I just would rather quit than keep trying. But someone said this helps majorly so I was wondering if any of you have tried it. If so, did you dilute or use it full on? (Its also super expensive)  I use 7th stages by clairol with a vol 30. I don't want any vol 40 nonsense either so... My natural/roots are a med-dark brown.

Also, supposedly you should use their developer but I find that's the company trying to make $ as most developers are fairly similar and I already have a gentle one. Do you think I would need to buy it? And also, if the lift is greater for that bleach powder, should I go lower in peroxide %/vol? Meaning I heard you can get great lift with the Blonde Me and 20vol as opposed to 30.

While searching for it, I also found posts about the Nordic? Any recs on the best bleach? I thought mine was good but if there's a better way that's not much more damaging maybe I could try...

Thanks!