You can always try it out and if you don't like it, just remove them, as they don't need to be glued on...
I hate way too much salt spray without them, now I just get a bit of creep out of the holes, which are probably 1/4", you could drill bigger holes.
my LFS sells the filter bags, but you can go on the Precision Marine website and buy them on line, they are 100 micron bags, with nice handles built in and a solid ring that keeps them open.
http://www.precisionmarinedirect.com/store/viewItem.asp?idProduct=739