Since space under the hood is limited it's difficult to lower pressure drop across the filter (i.e., increase flow) via low air/cloth ratio (low face velocity) by increasing filter surface area. You can increase it a little through deeper pleating but if you really want high flow then your only option is to increase porosity, which reduces collection efficiency. There's the tradeoff. The only "free lunch" you get is through oiling like K&N. What they offer is a filter that is more porous than stock - which ordinarily would reduce collection efficiency - but since the fibers are coated with sticky oil, particles are more likely to impinge upon them and not get re-entrained. Unfortunately oil doesn't help steel mesh filters much in the long run since they aren't very absorbent. A lot of the oil will initially get sucked into the intake and burn. The oil that remains will be in low velocity areas that would would ordinarily take up the slack when a good dust cake begins to build in the higher flow areas. As pressure drop across the filter rises due to less surface area, the filter will "blind" and you'll get larger particles passing through than if you had just left the thing dry.

What I would do if I had one of those cone filters is run a Filter Skin on it most of the time to trap fine particles and when I felt the urge to show off my underhood jewels or get that last 0.5 horsepower out of the VX, I'd take the skin off...