I'm more of a hit and miss guy when it comes to filters, when I have the room for them I use them. When I use them they are the crap trap filters. My fuel jug line is also filtered by a crap trap. So far I have never had any fuel flow problems with an engine but I have found some mystery floaters inside the YS diaphrams, no problems but there was nasty crap in there. A filter doesn't hurt anything so it's one of those up to the pilot things. I find a carb filter is needed more on my planes then a fuel filter, I have found some real nasty inside the engine during cleaning, I fly mostly off of a dirt runway so I can suck up sone very odd stuff.