Put it this way, I currently only use Kryston Meltdown PVA for string, ESP for bags, and Fox Mesh. Their claims are correct, not all of the others are.
In fact sad to say, after an incident with Nash PVA I will never use that brand again. I left a packet of bags in my trouser pocket as they went through the washing machine on a 40 degree wash. The bag at the end had water in, the PVA was still undissolved.
I did used to use Mo's co PVA, but sadly he stopped trading, and obviously now I work in a tackle shop I get my PVA at staff price, not rrp, so have no need to go via T'internet.