DS has never liked the mesh feeder. I first tried to give it to him when he was 7 months old (fresh watermelon first and then frozen mango), but he did not like it. I've tried several times since, especially when he was teething, but still nada. I just think he doesn't like the texture of the mesh.
Re: mango in the mesh feeder?
I've done frozen for teething. I had a hard time cleaning it out, but I'm one of those who are mesh-feeder-cleaning-impared.
Mango can cause skin irritation, so you may not want to do it in the mesh feeder.
We did it starting at around 6 months... It helped with teething and he LOVED it.
ETA: Frozen.. we've never done fresh.