Zip repair kits

Has anyone experience of zip repair kits?
I have a relatively little used Ron Hill waterproof jacket on which the zipper has come off, never to be seen again.
There are plenty of kits available from the usual online sources but all of them seem to somewhere have a comment that the metal is of poor quality (the original zip is totally orange plastic). Can anyone recommend a repair kit that is of durable quality.
I am lucky that I am married to someone who will be able to fit it without too much trouble.
Thanks in advance
Gordon