Has anyone used screwfix "Post Anchor Base" to secure raised decking posts?

They are much cheaper than the metpost type, 1.49 GBP compared to 4.50 GBP,
but do they give as solid a result.

http://www.screwfix.com/app/sfd/cat/...36841&id=56830

http://www.screwfix.com/app/sfd/cat/...36841&id=32806

Many thanks
Roger