Whilst having a two-storey extension to our ugly 1970s box, we have taken the opportunity to replace all the gutters/fascias with upvc ones. The angle of the roof is quite shallow and we get a fair amount of moss on the roof - particularly on the north side.
The fascia installers and roofers have both (independently from each other) suggested we put hedgehogs in the gutters. The roofer said that although the roof has a fair amount of moss on it, it is by no means a problem. He also said that he wouldn't recommend any chemical coating to kill the moss/prevent growth - particularly has we have water butts.
The scaffolding is coming down in about a week, so if we are going to fit them then the ideal time would be while it is still here. We, therefore, don't have time to do loads of research.
So, are they any good? Will they REALLY stop the gutters blocking up as quickly? Do they REALLY only need to be cleaned out every 5 years?