The whole issue of paint sealants and whether or not they're worth spending money on fills an awful lot of the Internet, that's for sure.

For what it's worth I wouldn't bother with it, and certainly not for the outside of whatever vehicle it is. I wouldn't go as far as to suggest that these things are all snake oil, but I can't help feeling that there is a degree of disingenuousness when companies claim that the 'Teflon (or PTFE)-based' coating 'bonds' to the surface, making it 'repel' dirt and stains and sap and bird doings and smushed insects and stuff.

If nothing sticks to Teflon, how does the Teflon stick to whatever you apply it to?

Apparently a PTFE coating can be made to bond to a surface, but that bonding involves a temperature well in excess of 300°C...

The issue that Eric alluded to is another one entirely, and there are many, many tales - some anecdotal, some not - of the mark up (dealer profit) involved. I'd be surprised if a dealer paid anywhere near as much as you'd get charged if you arranged to get the treatment done yourself.

On the other hand, a less cynical cove might point to the number of peeps who are absolutely delighted with their paint treatment and feel that it was worth every penny of the four hundred notes it cost.

If you were thinking of going down the self-application route (rather than pay someone else the bulk of that £400 for their labour), one thing worth considering is that the key word is preparation.

The item being treated must be scrupulously clean - like no wax residue or anything - and you should really do it inside a building where dust and grit can't be blown on to the surface while you're busily buffing. Lots of new car owners - lots of new car owners - have complained that after the treatment their pride and joy has swirls and scratches sealed into the finish thanks to poor preparation by supposedly professional valeters.

I'd stick with spending an awful lot less on some good quality car shampoo, polish and wax, two new black rubber buckets, a handful of sponges and an armful of decent microfibre cloths.

I reckon there really isn't a shortcut to cleaning a vehicle properly. If you buy something that promises you only have to clean once every umpteen years, you miss out on the opportunity to check for the stone chips and other damage that you would spot immediately in the course of routine cleaning.

And one last thing. These 'professionally-applied' sealants come with a five year guarantee. A five year guarantee of what, exactly? A five year guarantee that your caravan won't get dirty or that if you happen to be following a muckspreader down a country lane all the cowsh*t will just fall off?

I think if I were you I'd save my money and spend it on something really useful like wine.

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