I prefer the felt as they are easier to clean. If you have sufficient other measures in place for filtration ie; good skimmer, carbon/GFO reactor the felt should be sufficient. If not then go with the mesh they seem to filter out a little bit more than the felt IMO.
I think you might have mistaken the names of the socks kschweer. The mesh is not nearly as hard to clean as felt. Felt is going to clog very fast compared to the mesh. If you are the kind of lazy guy go with the mesh as you don't have to clean it as often if you are planning on changing it out every other day then get the felt as it traps everything!! I use felt and tried the mesh and returned them. BRS has a great picture where you can see the difference in the 2.