Here are my before & afters of the Wella T15 Toner. The first was done on yellow hair, and the second on orange. Neither of these photos have been edited, so you can see the true results that I achieved with the toner.
WELLA T15 TONER ON BLEACHED OR YELLOW HAIR
You'll see in the first before and after above, that the Wella T15 is beautiful on bleached or yellow hair - in fact, this is what it's designed for! You'll see that the after result is a slightly blonde darker and doesn't have any brassiness, while adding some lovely warm tones. In some lights, I can see a very slight pinky tone on the after - it's really nice!
WELLA T15 TONER ON ORANGE HAIR
I've also created a before and after of the Wella T15 on orange hair - you'll see it above. The Wella T15 is really designed for hair that's lighter than the orange, so you won't get the full effect of the toner. However, you will see that it's reduced some of the brassiness while keeping the hair a warm tone.
WELLA T15 TONER ON GREY HAIR
As the Wella T15 Toner is a light, beige blonde toner - it'll bring warmth back into your grey hair. For a more natural result on grey hair, I'd recommend mixing the Wella T15 Toner with the Wella T18 Toner. This will keep in some silvery ashiness, while giving you that beautiful warm blonde you desire - a much more natural result than using either of these toners alone!