I'm not sure I understand why some people think that SFS is too delicate. I'm a newbie and I've never felt as if I've been in danger of ripping the unit.

I can see on the other hand, that some people might prefer more durability. I don't think that I can make my current units last more than three or four months. They've been cut down from a larger size, and so the edges start to fray after two months or so. I'm not sure if this is an issue if the unit is unit is custom and hasn't been cut to a smaller size, though. If the edges weren't fraying, I think I could make an SFS unit last even longer.