Looks good, Mike. I like the £10 voucher, but not sure you should be making such a fuss about the noise. Most people are out all day and won't have witnessed the noise you made and will just imagine some exhaust spewing machine outside their hose and be utterly put off by the prospect.
The noise, if you can call it noise, is something that makes people look at what's going on and see your van, all of which is good. But to emphasise the noise aspect seems to be advertising a negative because you're apologising for it. Why not invite them to call round and look at the quality of what you've done.
Simon
Simon